diff --git a/docs/modules/ROOT/pages/concepts/counters.adoc b/docs/modules/ROOT/pages/concepts/counters.adoc
index fffe04f66c..1a552f4384 100644
--- a/docs/modules/ROOT/pages/concepts/counters.adoc
+++ b/docs/modules/ROOT/pages/concepts/counters.adoc
@@ -50,8 +50,6 @@ Counter counter = Counter
 
 The `micrometer-core` module contains a `@Counted` annotation that frameworks can use to add counting support to either specific types of methods such as those serving web request endpoints or, more generally, to all methods.
 
-WARNING: Micrometer's Spring Boot configuration does _not_ recognize `@Counted` on arbitrary methods.
-
 Also, an incubating AspectJ aspect is included in `micrometer-core`. You can use it in your application either through compile/load time AspectJ weaving or through framework facilities that interpret AspectJ aspects and proxy targeted methods in some other way, such as Spring AOP. Here is a sample Spring AOP configuration:
 
 [source,java]
diff --git a/docs/modules/ROOT/pages/concepts/timers.adoc b/docs/modules/ROOT/pages/concepts/timers.adoc
index 03f98825f3..d5efd25519 100644
--- a/docs/modules/ROOT/pages/concepts/timers.adoc
+++ b/docs/modules/ROOT/pages/concepts/timers.adoc
@@ -73,8 +73,6 @@ Note how we do not decide the timer to which to accumulate the sample until it i
 
 The `micrometer-core` module contains a `@Timed` annotation that frameworks can use to add timing support to either specific types of methods such as those serving web request endpoints or, more generally, to all methods.
 
-WARNING: Micrometer's Spring Boot configuration does _not_ recognize `@Timed` on arbitrary methods.
-
 Also, an incubating AspectJ aspect is included in `micrometer-core`. You can use it in your application either through compile/load time AspectJ weaving or through framework facilities that interpret AspectJ aspects and proxy targeted methods in some other way, such as Spring AOP. Here is a sample Spring AOP configuration:
 
 [source,java]
diff --git a/docs/src/test/java/io/micrometer/docs/metrics/TimedAspectTest.java b/docs/src/test/java/io/micrometer/docs/metrics/TimedAspectTest.java
index 77fcb77e88..7539097ac3 100644
--- a/docs/src/test/java/io/micrometer/docs/metrics/TimedAspectTest.java
+++ b/docs/src/test/java/io/micrometer/docs/metrics/TimedAspectTest.java
@@ -40,7 +40,7 @@ class TimedAspectTest {
     // end::resolvers[]
 
     @ParameterizedTest
-    @EnumSource(AnnotatedTestClass.class)
+    @EnumSource
     void meterTagsWithText(AnnotatedTestClass annotatedClass) {
         MeterRegistry registry = new SimpleMeterRegistry();
         TimedAspect timedAspect = new TimedAspect(registry);
@@ -63,7 +63,7 @@ void meterTagsWithText(AnnotatedTestClass annotatedClass) {
     }
 
     @ParameterizedTest
-    @EnumSource(AnnotatedTestClass.class)
+    @EnumSource
     void meterTagsWithResolver(AnnotatedTestClass annotatedClass) {
         MeterRegistry registry = new SimpleMeterRegistry();
         TimedAspect timedAspect = new TimedAspect(registry);
@@ -88,7 +88,7 @@ void meterTagsWithResolver(AnnotatedTestClass annotatedClass) {
     }
 
     @ParameterizedTest
-    @EnumSource(AnnotatedTestClass.class)
+    @EnumSource
     void meterTagsWithExpression(AnnotatedTestClass annotatedClass) {
         MeterRegistry registry = new SimpleMeterRegistry();
         TimedAspect timedAspect = new TimedAspect(registry);
diff --git a/implementations/micrometer-registry-statsd/src/test/java/io/micrometer/statsd/StatsdMeterRegistryPublishTest.java b/implementations/micrometer-registry-statsd/src/test/java/io/micrometer/statsd/StatsdMeterRegistryPublishTest.java
index 36e4e21db7..ae1d89fb6e 100644
--- a/implementations/micrometer-registry-statsd/src/test/java/io/micrometer/statsd/StatsdMeterRegistryPublishTest.java
+++ b/implementations/micrometer-registry-statsd/src/test/java/io/micrometer/statsd/StatsdMeterRegistryPublishTest.java
@@ -80,7 +80,7 @@ void cleanUp() {
     }
 
     @ParameterizedTest
-    @EnumSource(StatsdProtocol.class)
+    @EnumSource
     void receiveAllBufferedMetricsAfterCloseSuccessfully(StatsdProtocol protocol) throws InterruptedException {
         skipUdsTestOnWindows(protocol);
         serverLatch = new CountDownLatch(3);
@@ -98,7 +98,7 @@ void receiveAllBufferedMetricsAfterCloseSuccessfully(StatsdProtocol protocol) th
     }
 
     @ParameterizedTest
-    @EnumSource(StatsdProtocol.class)
+    @EnumSource
     void receiveMetricsSuccessfully(StatsdProtocol protocol) throws InterruptedException {
         skipUdsTestOnWindows(protocol);
         serverLatch = new CountDownLatch(3);
@@ -116,7 +116,7 @@ void receiveMetricsSuccessfully(StatsdProtocol protocol) throws InterruptedExcep
     }
 
     @ParameterizedTest
-    @EnumSource(StatsdProtocol.class)
+    @EnumSource
     void resumeSendingMetrics_whenServerIntermittentlyFails(StatsdProtocol protocol) throws InterruptedException {
         skipUdsTestOnWindows(protocol);
         serverLatch = new CountDownLatch(1);
@@ -163,7 +163,7 @@ void resumeSendingMetrics_whenServerIntermittentlyFails(StatsdProtocol protocol)
     }
 
     @ParameterizedTest
-    @EnumSource(StatsdProtocol.class)
+    @EnumSource
     @Issue("#1676")
     void stopAndStartMeterRegistrySendsMetrics(StatsdProtocol protocol) throws InterruptedException {
         skipUdsTestOnWindows(protocol);
@@ -206,7 +206,7 @@ void stopAndStartMeterRegistryWithLineSink() throws InterruptedException {
     }
 
     @ParameterizedTest
-    @EnumSource(StatsdProtocol.class)
+    @EnumSource
     void whenBackendInitiallyDown_metricsSentAfterBackendStarts(StatsdProtocol protocol) throws InterruptedException {
         skipUdsTestOnWindows(protocol);
         AtomicInteger writeCount = new AtomicInteger();
@@ -245,7 +245,7 @@ void whenBackendInitiallyDown_metricsSentAfterBackendStarts(StatsdProtocol proto
     }
 
     @ParameterizedTest
-    @EnumSource(StatsdProtocol.class)
+    @EnumSource
     void whenRegistryStopped_doNotConnectToBackend(StatsdProtocol protocol) throws InterruptedException {
         skipUdsTestOnWindows(protocol);
         serverLatch = new CountDownLatch(3);
@@ -264,7 +264,7 @@ void whenRegistryStopped_doNotConnectToBackend(StatsdProtocol protocol) throws I
     }
 
     @ParameterizedTest
-    @EnumSource(StatsdProtocol.class)
+    @EnumSource
     @Issue("#2177")
     void whenSendError_reconnectsAndWritesNewMetrics(StatsdProtocol protocol) throws InterruptedException {
         skipUdsTestOnWindows(protocol);
@@ -296,7 +296,7 @@ public void write(ChannelHandlerContext ctx, Object msg, ChannelPromise promise)
 
     @Issue("#2880")
     @ParameterizedTest
-    @EnumSource(StatsdProtocol.class)
+    @EnumSource
     void receiveParallelMetricsSuccessfully(StatsdProtocol protocol) throws InterruptedException {
         final int n = 10;
 
diff --git a/implementations/micrometer-registry-statsd/src/test/java/io/micrometer/statsd/StatsdMeterRegistryTest.java b/implementations/micrometer-registry-statsd/src/test/java/io/micrometer/statsd/StatsdMeterRegistryTest.java
index c3fc93166a..582d6cca98 100644
--- a/implementations/micrometer-registry-statsd/src/test/java/io/micrometer/statsd/StatsdMeterRegistryTest.java
+++ b/implementations/micrometer-registry-statsd/src/test/java/io/micrometer/statsd/StatsdMeterRegistryTest.java
@@ -79,7 +79,7 @@ public StatsdFlavor flavor() {
     }
 
     @ParameterizedTest
-    @EnumSource(StatsdFlavor.class)
+    @EnumSource
     void counterLineProtocol(StatsdFlavor flavor) {
         String line = null;
         switch (flavor) {
@@ -112,7 +112,7 @@ void counterLineProtocol(StatsdFlavor flavor) {
     }
 
     @ParameterizedTest
-    @EnumSource(StatsdFlavor.class)
+    @EnumSource
     void gaugeLineProtocol(StatsdFlavor flavor) {
         final AtomicInteger n = new AtomicInteger(2);
         final StatsdConfig config = configWithFlavor(flavor);
@@ -145,7 +145,7 @@ void gaugeLineProtocol(StatsdFlavor flavor) {
     }
 
     @ParameterizedTest
-    @EnumSource(StatsdFlavor.class)
+    @EnumSource
     void timerLineProtocol(StatsdFlavor flavor) {
         String line = null;
         switch (flavor) {
@@ -178,7 +178,7 @@ void timerLineProtocol(StatsdFlavor flavor) {
     }
 
     @ParameterizedTest
-    @EnumSource(StatsdFlavor.class)
+    @EnumSource
     void summaryLineProtocol(StatsdFlavor flavor) {
         String line = null;
         switch (flavor) {
@@ -211,7 +211,7 @@ void summaryLineProtocol(StatsdFlavor flavor) {
     }
 
     @ParameterizedTest
-    @EnumSource(StatsdFlavor.class)
+    @EnumSource
     void longTaskTimerLineProtocol(StatsdFlavor flavor) {
         final StatsdConfig config = configWithFlavor(flavor);
         long stepMillis = config.step().toMillis();
@@ -286,7 +286,7 @@ void counterIncrementDoesNotCauseStackOverflow() {
     }
 
     @ParameterizedTest
-    @EnumSource(StatsdFlavor.class)
+    @EnumSource
     @Issue("#370")
     void serviceLevelObjectivesOnlyNoPercentileHistogram(StatsdFlavor flavor) {
         StatsdConfig config = configWithFlavor(flavor);
@@ -390,7 +390,7 @@ void interactWithStoppedRegistry() {
     }
 
     @ParameterizedTest
-    @EnumSource(StatsdFlavor.class)
+    @EnumSource
     @Issue("#600")
     void memoryPerformanceOfNamingConventionInHotLoops(StatsdFlavor flavor) {
         AtomicInteger namingConventionUses = new AtomicInteger();
diff --git a/micrometer-core/src/main/java/io/micrometer/core/aop/CountedAspect.java b/micrometer-core/src/main/java/io/micrometer/core/aop/CountedAspect.java
index c0f199e38c..fcddc4cc2b 100644
--- a/micrometer-core/src/main/java/io/micrometer/core/aop/CountedAspect.java
+++ b/micrometer-core/src/main/java/io/micrometer/core/aop/CountedAspect.java
@@ -71,6 +71,7 @@
  * @author Jonatan Ivanov
  * @author Johnny Lim
  * @author Yanming Zhou
+ * @author Jeonggi Kim
  * @since 1.2.0
  * @see Counted
  */
@@ -237,8 +238,17 @@ private Object perform(ProceedingJoinPoint pjp, Counted counted) throws Throwabl
 
         if (stopWhenCompleted) {
             try {
-                return ((CompletionStage<?>) pjp.proceed())
-                    .whenComplete((result, throwable) -> recordCompletionResult(pjp, counted, throwable));
+                Object result = pjp.proceed();
+                if (result == null) {
+                    if (!counted.recordFailuresOnly()) {
+                        record(pjp, counted, DEFAULT_EXCEPTION_TAG_VALUE, RESULT_TAG_SUCCESS_VALUE);
+                    }
+                    return result;
+                }
+                else {
+                    CompletionStage<?> stage = ((CompletionStage<?>) result);
+                    return stage.whenComplete((res, throwable) -> recordCompletionResult(pjp, counted, throwable));
+                }
             }
             catch (Throwable e) {
                 record(pjp, counted, e.getClass().getSimpleName(), RESULT_TAG_FAILURE_VALUE);
diff --git a/micrometer-core/src/main/java/io/micrometer/core/aop/TimedAspect.java b/micrometer-core/src/main/java/io/micrometer/core/aop/TimedAspect.java
index ee51c7f0a8..fc2138d839 100644
--- a/micrometer-core/src/main/java/io/micrometer/core/aop/TimedAspect.java
+++ b/micrometer-core/src/main/java/io/micrometer/core/aop/TimedAspect.java
@@ -82,6 +82,7 @@
  * @author Nejc Korasa
  * @author Jonatan Ivanov
  * @author Yanming Zhou
+ * @author Jeonggi Kim
  * @since 1.0.0
  */
 @Aspect
@@ -235,8 +236,16 @@ private Object processWithTimer(ProceedingJoinPoint pjp, Timed timed, String met
 
         if (stopWhenCompleted) {
             try {
-                return ((CompletionStage<?>) pjp.proceed()).whenComplete(
-                        (result, throwable) -> record(pjp, timed, metricName, sample, getExceptionTag(throwable)));
+                Object result = pjp.proceed();
+                if (result == null) {
+                    record(pjp, timed, metricName, sample, DEFAULT_EXCEPTION_TAG_VALUE);
+                    return result;
+                }
+                else {
+                    CompletionStage<?> stage = ((CompletionStage<?>) result);
+                    return stage.whenComplete(
+                            (res, throwable) -> record(pjp, timed, metricName, sample, getExceptionTag(throwable)));
+                }
             }
             catch (Throwable e) {
                 record(pjp, timed, metricName, sample, e.getClass().getSimpleName());
@@ -307,8 +316,15 @@ private Object processWithLongTaskTimer(ProceedingJoinPoint pjp, Timed timed, St
 
         if (stopWhenCompleted) {
             try {
-                return ((CompletionStage<?>) pjp.proceed())
-                    .whenComplete((result, throwable) -> sample.ifPresent(this::stopTimer));
+                Object result = pjp.proceed();
+                if (result == null) {
+                    sample.ifPresent(this::stopTimer);
+                    return result;
+                }
+                else {
+                    CompletionStage<?> stage = ((CompletionStage<?>) result);
+                    return stage.whenComplete((res, throwable) -> sample.ifPresent(this::stopTimer));
+                }
             }
             catch (Throwable e) {
                 sample.ifPresent(this::stopTimer);
diff --git a/micrometer-core/src/test/java/io/micrometer/core/instrument/binder/cache/CaffeineStatsCounterTest.java b/micrometer-core/src/test/java/io/micrometer/core/instrument/binder/cache/CaffeineStatsCounterTest.java
index 358969bd7c..b10fb495a6 100644
--- a/micrometer-core/src/test/java/io/micrometer/core/instrument/binder/cache/CaffeineStatsCounterTest.java
+++ b/micrometer-core/src/test/java/io/micrometer/core/instrument/binder/cache/CaffeineStatsCounterTest.java
@@ -94,7 +94,7 @@ void loadFailure() {
     }
 
     @ParameterizedTest
-    @EnumSource(RemovalCause.class)
+    @EnumSource
     void evictionWithCause(RemovalCause cause) {
         stats.recordEviction(3, cause);
         DistributionSummary summary = fetch("cache.evictions", "cause", cause.name()).summary();
diff --git a/micrometer-observation/src/main/java/io/micrometer/observation/aop/ObservedAspect.java b/micrometer-observation/src/main/java/io/micrometer/observation/aop/ObservedAspect.java
index 080692ee1a..c6d7d4fdb8 100644
--- a/micrometer-observation/src/main/java/io/micrometer/observation/aop/ObservedAspect.java
+++ b/micrometer-observation/src/main/java/io/micrometer/observation/aop/ObservedAspect.java
@@ -70,6 +70,7 @@
  *
  * @author Jonatan Ivanov
  * @author Yanming Zhou
+ * @author Jeonggi Kim
  * @since 1.10.0
  */
 @Aspect
@@ -148,8 +149,15 @@ private Object observe(ProceedingJoinPoint pjp, Method method, Observed observed
             observation.start();
             Observation.Scope scope = observation.openScope();
             try {
-                return ((CompletionStage<?>) pjp.proceed())
-                    .whenComplete((result, error) -> stopObservation(observation, scope, error));
+                Object result = pjp.proceed();
+                if (result == null) {
+                    stopObservation(observation, scope, null);
+                    return result;
+                }
+                else {
+                    CompletionStage<?> stage = (CompletionStage<?>) result;
+                    return stage.whenComplete((res, error) -> stopObservation(observation, scope, error));
+                }
             }
             catch (Throwable error) {
                 stopObservation(observation, scope, error);
diff --git a/micrometer-test/src/main/java/io/micrometer/core/instrument/HttpClientTimingInstrumentationVerificationTests.java b/micrometer-test/src/main/java/io/micrometer/core/instrument/HttpClientTimingInstrumentationVerificationTests.java
index 945c3e18fb..67a0bd0a94 100644
--- a/micrometer-test/src/main/java/io/micrometer/core/instrument/HttpClientTimingInstrumentationVerificationTests.java
+++ b/micrometer-test/src/main/java/io/micrometer/core/instrument/HttpClientTimingInstrumentationVerificationTests.java
@@ -144,7 +144,7 @@ protected String substitutePathVariables(String templatedPath, String... pathVar
     }
 
     @ParameterizedTest
-    @EnumSource(TestType.class)
+    @EnumSource
     void getTemplatedPathForUri(TestType testType, WireMockRuntimeInfo wmRuntimeInfo) {
         checkAndSetupTestForTestType(testType);
 
@@ -162,7 +162,7 @@ void getTemplatedPathForUri(TestType testType, WireMockRuntimeInfo wmRuntimeInfo
     }
 
     @ParameterizedTest
-    @EnumSource(TestType.class)
+    @EnumSource
     @Disabled("apache/jetty http client instrumentation currently fails this test")
     void timedWhenServerIsMissing(TestType testType) throws IOException {
         checkAndSetupTestForTestType(testType);
@@ -186,7 +186,7 @@ void timedWhenServerIsMissing(TestType testType) throws IOException {
     }
 
     @ParameterizedTest
-    @EnumSource(TestType.class)
+    @EnumSource
     void serverException(TestType testType, WireMockRuntimeInfo wmRuntimeInfo) {
         checkAndSetupTestForTestType(testType);
 
@@ -203,7 +203,7 @@ void serverException(TestType testType, WireMockRuntimeInfo wmRuntimeInfo) {
     }
 
     @ParameterizedTest
-    @EnumSource(TestType.class)
+    @EnumSource
     void clientException(TestType testType, WireMockRuntimeInfo wmRuntimeInfo) {
         checkAndSetupTestForTestType(testType);
 
@@ -223,7 +223,7 @@ void clientException(TestType testType, WireMockRuntimeInfo wmRuntimeInfo) {
     // TODO this test doesn't need to be parameterized but the custom resolver for
     // Before/After methods doesn't like when it isn't.
     @ParameterizedTest
-    @EnumSource(TestType.class)
+    @EnumSource
     void headerIsPropagatedFromContext(TestType testType, WireMockRuntimeInfo wmRuntimeInfo) {
         checkAndSetupTestForTestType(testType);
 
diff --git a/micrometer-test/src/main/java/io/micrometer/core/instrument/HttpServerTimingInstrumentationVerificationTests.java b/micrometer-test/src/main/java/io/micrometer/core/instrument/HttpServerTimingInstrumentationVerificationTests.java
index 2b304d9aec..075fe118c9 100644
--- a/micrometer-test/src/main/java/io/micrometer/core/instrument/HttpServerTimingInstrumentationVerificationTests.java
+++ b/micrometer-test/src/main/java/io/micrometer/core/instrument/HttpServerTimingInstrumentationVerificationTests.java
@@ -120,14 +120,14 @@ void afterEach() throws Exception {
     }
 
     @ParameterizedTest
-    @EnumSource(TestType.class)
+    @EnumSource
     void uriIsNotFound_whenRouteIsUnmapped(TestType testType) throws Throwable {
         sender.get(baseUri + "notFound").send();
         checkTimer(rs -> rs.tags("uri", "NOT_FOUND", "status", "404", "method", "GET").timer().count() == 1);
     }
 
     @ParameterizedTest
-    @EnumSource(TestType.class)
+    @EnumSource
     void uriTemplateIsTagged(TestType testType) throws Throwable {
         sender.get(baseUri + "hello/world").send();
         checkTimer(rs -> rs.tags("uri", InstrumentedRoutes.TEMPLATED_ROUTE, "status", "200", "method", "GET")
@@ -136,7 +136,7 @@ void uriTemplateIsTagged(TestType testType) throws Throwable {
     }
 
     @ParameterizedTest
-    @EnumSource(TestType.class)
+    @EnumSource
     void redirect(TestType testType) throws Throwable {
         sender.get(baseUri + "foundRedirect").send();
         checkTimer(rs -> rs.tags("uri", InstrumentedRoutes.REDIRECT, "status", "302", "method", "GET")
@@ -145,7 +145,7 @@ void redirect(TestType testType) throws Throwable {
     }
 
     @ParameterizedTest
-    @EnumSource(TestType.class)
+    @EnumSource
     void errorResponse(TestType testType) throws Throwable {
         sender.post(baseUri + "error").send();
         checkTimer(
@@ -153,7 +153,7 @@ void errorResponse(TestType testType) throws Throwable {
     }
 
     @ParameterizedTest
-    @EnumSource(TestType.class)
+    @EnumSource
     void canExtractContextFromHeaders(TestType testType) throws Throwable {
         sender.get(baseUri + "hello/micrometer").withHeader("Test-Propagation", "someValue").send();
 
diff --git a/micrometer-test/src/main/java/io/micrometer/core/ipc/http/HttpSenderCompatibilityKit.java b/micrometer-test/src/main/java/io/micrometer/core/ipc/http/HttpSenderCompatibilityKit.java
index a81ecc24ea..5cfbd5d84a 100644
--- a/micrometer-test/src/main/java/io/micrometer/core/ipc/http/HttpSenderCompatibilityKit.java
+++ b/micrometer-test/src/main/java/io/micrometer/core/ipc/http/HttpSenderCompatibilityKit.java
@@ -56,7 +56,7 @@ void httpSenderIsNotNull() {
 
     @ParameterizedTest
     @DisplayName("successfully send a request with NO body and receive a response with NO body")
-    @EnumSource(HttpSender.Method.class)
+    @EnumSource
     void successfulRequestSentWithNoBody(HttpSender.Method method, @WiremockResolver.Wiremock WireMockServer server)
             throws Throwable {
         server.stubFor(any(urlEqualTo("/metrics")));
@@ -104,7 +104,7 @@ void successfulRequestSentWithBody(HttpSender.Method method, @WiremockResolver.W
 
     @ParameterizedTest
     @DisplayName("receive an error response")
-    @EnumSource(HttpSender.Method.class)
+    @EnumSource
     void errorResponseReceived(HttpSender.Method method, @WiremockResolver.Wiremock WireMockServer server)
             throws Throwable {
         server.stubFor(any(urlEqualTo("/metrics")).willReturn(badRequest().withBody("Error processing metrics")));
@@ -121,7 +121,7 @@ void errorResponseReceived(HttpSender.Method method, @WiremockResolver.Wiremock
     }
 
     @ParameterizedTest
-    @EnumSource(HttpSender.Method.class)
+    @EnumSource
     void basicAuth(HttpSender.Method method, @WiremockResolver.Wiremock WireMockServer server) throws Throwable {
         server.stubFor(any(urlEqualTo("/metrics")).willReturn(unauthorized()));
 
@@ -140,7 +140,7 @@ void basicAuth(HttpSender.Method method, @WiremockResolver.Wiremock WireMockServ
     }
 
     @ParameterizedTest
-    @EnumSource(HttpSender.Method.class)
+    @EnumSource
     void customHeader(HttpSender.Method method, @WiremockResolver.Wiremock WireMockServer server) throws Throwable {
         server.stubFor(any(urlEqualTo("/metrics")).willReturn(unauthorized()));
 
diff --git a/samples/micrometer-samples-spring-framework6/src/test/java/io/micrometer/samples/spring6/aop/CountedAspectTest.java b/samples/micrometer-samples-spring-framework6/src/test/java/io/micrometer/samples/spring6/aop/CountedAspectTest.java
index e0b730b250..0f2e004837 100644
--- a/samples/micrometer-samples-spring-framework6/src/test/java/io/micrometer/samples/spring6/aop/CountedAspectTest.java
+++ b/samples/micrometer-samples-spring-framework6/src/test/java/io/micrometer/samples/spring6/aop/CountedAspectTest.java
@@ -258,6 +258,27 @@ void pjpFunctionThrows() {
         assertThat(counter.getId().getDescription()).isNull();
     }
 
+    @Test
+    void countedWithSuccessfulMetricsWhenReturnsCompletionStageNull() {
+        CompletableFuture<?> completableFuture = asyncCountedService.successButNull();
+        assertThat(completableFuture).isNull();
+        assertThat(meterRegistry.get("metric.success")
+            .tag("method", "successButNull")
+            .tag("class", getClass().getName() + "$AsyncCountedService")
+            .tag("extra", "tag")
+            .tag("exception", "none")
+            .tag("result", "success")
+            .counter()
+            .count()).isOne();
+    }
+
+    @Test
+    void countedWithoutSuccessfulMetricsWhenReturnsCompletionStageNull() {
+        CompletableFuture<?> completableFuture = asyncCountedService.successButNullWithoutMetrics();
+        assertThat(completableFuture).isNull();
+        assertThatThrownBy(() -> meterRegistry.get("metric.none").counter()).isInstanceOf(MeterNotFoundException.class);
+    }
+
     static class CountedService {
 
         @Counted(value = "metric.none", recordFailuresOnly = true)
@@ -323,6 +344,16 @@ CompletableFuture<?> emptyMetricName(GuardedResult guardedResult) {
             return supplyAsync(guardedResult::get);
         }
 
+        @Counted(value = "metric.success", extraTags = { "extra", "tag" })
+        CompletableFuture<?> successButNull() {
+            return null;
+        }
+
+        @Counted(value = "metric.none", recordFailuresOnly = true)
+        CompletableFuture<?> successButNullWithoutMetrics() {
+            return null;
+        }
+
     }
 
     static class GuardedResult {
@@ -441,7 +472,7 @@ class MeterTagsTests {
                 aClass -> valueResolver, aClass -> valueExpressionResolver);
 
         @ParameterizedTest
-        @EnumSource(AnnotatedTestClass.class)
+        @EnumSource
         void meterTagsWithText(AnnotatedTestClass annotatedClass) {
             MeterRegistry registry = new SimpleMeterRegistry();
             CountedAspect countedAspect = new CountedAspect(registry);
@@ -458,7 +489,7 @@ void meterTagsWithText(AnnotatedTestClass annotatedClass) {
         }
 
         @ParameterizedTest
-        @EnumSource(AnnotatedTestClass.class)
+        @EnumSource
         void meterTagsWithResolver(AnnotatedTestClass annotatedClass) {
             MeterRegistry registry = new SimpleMeterRegistry();
             CountedAspect countedAspect = new CountedAspect(registry);
@@ -478,7 +509,7 @@ void meterTagsWithResolver(AnnotatedTestClass annotatedClass) {
         }
 
         @ParameterizedTest
-        @EnumSource(AnnotatedTestClass.class)
+        @EnumSource
         void meterTagsWithExpression(AnnotatedTestClass annotatedClass) {
             MeterRegistry registry = new SimpleMeterRegistry();
             CountedAspect countedAspect = new CountedAspect(registry);
@@ -495,7 +526,7 @@ void meterTagsWithExpression(AnnotatedTestClass annotatedClass) {
         }
 
         @ParameterizedTest
-        @EnumSource(AnnotatedTestClass.class)
+        @EnumSource
         void multipleMeterTagsWithExpression(AnnotatedTestClass annotatedClass) {
             MeterRegistry registry = new SimpleMeterRegistry();
             CountedAspect countedAspect = new CountedAspect(registry);
@@ -516,7 +547,7 @@ void multipleMeterTagsWithExpression(AnnotatedTestClass annotatedClass) {
         }
 
         @ParameterizedTest
-        @EnumSource(AnnotatedTestClass.class)
+        @EnumSource
         void multipleMeterTagsWithinContainerWithExpression(AnnotatedTestClass annotatedClass) {
             MeterRegistry registry = new SimpleMeterRegistry();
             CountedAspect countedAspect = new CountedAspect(registry);
diff --git a/samples/micrometer-samples-spring-framework6/src/test/java/io/micrometer/samples/spring6/aop/ObservedAspectTests.java b/samples/micrometer-samples-spring-framework6/src/test/java/io/micrometer/samples/spring6/aop/ObservedAspectTests.java
index c3476d4b8e..a01ef02ac5 100644
--- a/samples/micrometer-samples-spring-framework6/src/test/java/io/micrometer/samples/spring6/aop/ObservedAspectTests.java
+++ b/samples/micrometer-samples-spring-framework6/src/test/java/io/micrometer/samples/spring6/aop/ObservedAspectTests.java
@@ -357,6 +357,25 @@ void ignoreClassLevelAnnotationIfMethodLevelPresent() {
             .hasContextualNameEqualTo("test.class#annotatedOnMethod");
     }
 
+    @Test
+    void annotatedAsyncClassCallWithNullShouldBeObserved() {
+        registry.observationConfig().observationHandler(new ObservationTextPublisher());
+        AspectJProxyFactory pf = new AspectJProxyFactory(new ObservedClassLevelAnnotatedService());
+        pf.addAspect(new ObservedAspect(registry));
+        ObservedClassLevelAnnotatedService service = pf.getProxy();
+        CompletableFuture<String> asyncResult = service.asyncNull();
+        assertThat(asyncResult).isNull();
+        assertThat(registry).doesNotHaveAnyRemainingCurrentObservation()
+            .hasSingleObservationThat()
+            .hasNameEqualTo("test.class")
+            .hasContextualNameEqualTo("test.class#call")
+            .hasLowCardinalityKeyValue("abc", "123")
+            .hasLowCardinalityKeyValue("test", "42")
+            .hasLowCardinalityKeyValue("class", ObservedClassLevelAnnotatedService.class.getName())
+            .hasLowCardinalityKeyValue("method", "asyncNull")
+            .doesNotHaveError();
+    }
+
     static class ObservedService {
 
         @Observed(name = "test.call", contextualName = "test#call",
@@ -445,6 +464,10 @@ CompletableFuture<String> async(FakeAsyncTask fakeAsyncTask) {
         void annotatedOnMethod() {
         }
 
+        CompletableFuture<String> asyncNull() {
+            return null;
+        }
+
     }
 
     static class FakeAsyncTask implements Supplier<String> {
diff --git a/samples/micrometer-samples-spring-framework6/src/test/java/io/micrometer/samples/spring6/aop/TimedAspectTest.java b/samples/micrometer-samples-spring-framework6/src/test/java/io/micrometer/samples/spring6/aop/TimedAspectTest.java
index 1afede1331..80b11cc955 100644
--- a/samples/micrometer-samples-spring-framework6/src/test/java/io/micrometer/samples/spring6/aop/TimedAspectTest.java
+++ b/samples/micrometer-samples-spring-framework6/src/test/java/io/micrometer/samples/spring6/aop/TimedAspectTest.java
@@ -264,6 +264,24 @@ void timeMethodWhenCompletedExceptionally() {
             .count()).isEqualTo(1);
     }
 
+    @Test
+    void timeMethodWhenReturnCompletionStageNull() {
+        MeterRegistry registry = new SimpleMeterRegistry();
+        AspectJProxyFactory pf = new AspectJProxyFactory(new AsyncTimedService());
+        pf.addAspect(new TimedAspect(registry));
+        AsyncTimedService service = pf.getProxy();
+        CompletableFuture<?> completableFuture = service.callNull();
+        assertThat(completableFuture).isNull();
+        assertThat(registry.getMeters()).isNotEmpty();
+        assertThat(registry.get("callNull")
+            .tag("class", getClass().getName() + "$AsyncTimedService")
+            .tag("method", "callNull")
+            .tag("extra", "tag")
+            .tag("exception", "none")
+            .timer()
+            .count()).isEqualTo(1);
+    }
+
     @Test
     void timeMethodWithLongTaskTimerWhenCompleted() {
         MeterRegistry registry = new SimpleMeterRegistry();
@@ -324,6 +342,27 @@ void timeMethodWithLongTaskTimerWhenCompletedExceptionally() {
             .activeTasks()).isEqualTo(0);
     }
 
+    @Test
+    void timeMethodWithLongTaskTimerWhenReturnCompletionStageNull() {
+        MeterRegistry registry = new SimpleMeterRegistry();
+        AspectJProxyFactory pf = new AspectJProxyFactory(new AsyncTimedService());
+        pf.addAspect(new TimedAspect(registry));
+        AsyncTimedService service = pf.getProxy();
+        CompletableFuture<?> completableFuture = service.longCallNull();
+        assertThat(completableFuture).isNull();
+        assertThat(registry.get("longCallNull")
+            .tag("class", getClass().getName() + "$AsyncTimedService")
+            .tag("method", "longCallNull")
+            .tag("extra", "tag")
+            .longTaskTimers()).hasSize(1);
+        assertThat(registry.find("longCallNull")
+            .tag("class", getClass().getName() + "$AsyncTimedService")
+            .tag("method", "longCallNull")
+            .tag("extra", "tag")
+            .longTaskTimer()
+            .activeTasks()).isEqualTo(0);
+    }
+
     @Test
     void timeMethodFailureWhenCompletedExceptionally() {
         MeterRegistry failingRegistry = new FailingMeterRegistry();
@@ -487,7 +526,7 @@ class MeterTagsTests {
                 aClass -> valueExpressionResolver);
 
         @ParameterizedTest
-        @EnumSource(AnnotatedTestClass.class)
+        @EnumSource
         void meterTagsWithText(AnnotatedTestClass annotatedClass) {
             MeterRegistry registry = new SimpleMeterRegistry();
             TimedAspect timedAspect = new TimedAspect(registry);
@@ -504,7 +543,7 @@ void meterTagsWithText(AnnotatedTestClass annotatedClass) {
         }
 
         @ParameterizedTest
-        @EnumSource(AnnotatedTestClass.class)
+        @EnumSource
         void meterTagsWithResolver(AnnotatedTestClass annotatedClass) {
             MeterRegistry registry = new SimpleMeterRegistry();
             TimedAspect timedAspect = new TimedAspect(registry);
@@ -524,7 +563,7 @@ void meterTagsWithResolver(AnnotatedTestClass annotatedClass) {
         }
 
         @ParameterizedTest
-        @EnumSource(AnnotatedTestClass.class)
+        @EnumSource
         void meterTagsWithExpression(AnnotatedTestClass annotatedClass) {
             MeterRegistry registry = new SimpleMeterRegistry();
             TimedAspect timedAspect = new TimedAspect(registry);
@@ -542,7 +581,7 @@ void meterTagsWithExpression(AnnotatedTestClass annotatedClass) {
         }
 
         @ParameterizedTest
-        @EnumSource(AnnotatedTestClass.class)
+        @EnumSource
         void multipleMeterTagsWithExpression(AnnotatedTestClass annotatedClass) {
             MeterRegistry registry = new SimpleMeterRegistry();
             TimedAspect timedAspect = new TimedAspect(registry);
@@ -563,7 +602,7 @@ void multipleMeterTagsWithExpression(AnnotatedTestClass annotatedClass) {
         }
 
         @ParameterizedTest
-        @EnumSource(AnnotatedTestClass.class)
+        @EnumSource
         void multipleMeterTagsWithinContainerWithExpression(AnnotatedTestClass annotatedClass) {
             MeterRegistry registry = new SimpleMeterRegistry();
             TimedAspect timedAspect = new TimedAspect(registry);
@@ -816,11 +855,21 @@ CompletableFuture<?> call(GuardedResult guardedResult) {
             return supplyAsync(guardedResult::get);
         }
 
+        @Timed(value = "callNull", extraTags = { "extra", "tag" })
+        CompletableFuture<?> callNull() {
+            return null;
+        }
+
         @Timed(value = "longCall", extraTags = { "extra", "tag" }, longTask = true)
         CompletableFuture<?> longCall(GuardedResult guardedResult) {
             return supplyAsync(guardedResult::get);
         }
 
+        @Timed(value = "longCallNull", extraTags = { "extra", "tag" }, longTask = true)
+        CompletableFuture<?> longCallNull() {
+            return null;
+        }
+
     }
 
     static class GuardedResult {