diff --git a/consensus/blake3pow/consensus.go b/consensus/blake3pow/consensus.go
index f0e6672edc..63c9da0755 100644
--- a/consensus/blake3pow/consensus.go
+++ b/consensus/blake3pow/consensus.go
@@ -366,8 +366,9 @@ func (blake3pow *Blake3pow) verifyHeader(chain consensus.ChainHeaderReader, head
 			if header.ThresholdCount() != 0 {
 				return fmt.Errorf("invalid threshold count: have %v, want %v", header.ThresholdCount(), 0)
 			}
-			if header.ExpansionNumber() != 0 {
-				return fmt.Errorf("invalid expansion number: have %v, want %v", header.ExpansionNumber(), 0)
+			genesisHeader := chain.GetHeaderByNumber(0)
+			if header.ExpansionNumber() != genesisHeader.ExpansionNumber() {
+				return fmt.Errorf("invalid expansion number: have %v, want %v", header.ExpansionNumber(), genesisHeader.ExpansionNumber())
 			}
 		} else {
 			expectedEfficiencyScore := chain.ComputeEfficiencyScore(parent)
@@ -503,6 +504,10 @@ func (blake3pow *Blake3pow) CalcDifficulty(chain consensus.ChainHeaderReader, pa
 			// Base case: expansion number is 0 and the parent is the actual genesis block
 			return parent.Difficulty()
 		}
+		genesisBlock := chain.GetHeaderByHash(parent.Hash())
+		if genesisBlock.ExpansionNumber() > 0 && parent.Hash() == chain.Config().DefaultGenesisHash {
+			return parent.Difficulty()
+		}
 		genesis := chain.GetHeaderByHash(parent.Hash())
 		genesisTotalLogS := blake3pow.TotalLogS(chain, genesis)
 		if genesisTotalLogS.Cmp(genesis.ParentEntropy(common.PRIME_CTX)) < 0 { // prevent negative difficulty
diff --git a/consensus/progpow/consensus.go b/consensus/progpow/consensus.go
index 963c79b825..192a5297fa 100644
--- a/consensus/progpow/consensus.go
+++ b/consensus/progpow/consensus.go
@@ -362,8 +362,9 @@ func (progpow *Progpow) verifyHeader(chain consensus.ChainHeaderReader, header,
 			if header.ThresholdCount() != 0 {
 				return fmt.Errorf("invalid threshold count: have %v, want %v", header.ThresholdCount(), 0)
 			}
-			if header.ExpansionNumber() != 0 {
-				return fmt.Errorf("invalid expansion number: have %v, want %v", header.ExpansionNumber(), 0)
+			genesisHeader := chain.GetHeaderByNumber(0)
+			if header.ExpansionNumber() != genesisHeader.ExpansionNumber() {
+				return fmt.Errorf("invalid expansion number: have %v, want %v", header.ExpansionNumber(), genesisHeader.ExpansionNumber())
 			}
 		} else {
 			expectedEfficiencyScore := chain.ComputeEfficiencyScore(parent)
@@ -501,6 +502,10 @@ func (progpow *Progpow) CalcDifficulty(chain consensus.ChainHeaderReader, parent
 			// Base case: expansion number is 0 and the parent is the actual genesis block
 			return parent.Difficulty()
 		}
+		genesisBlock := chain.GetHeaderByHash(parent.Hash())
+		if genesisBlock.ExpansionNumber() > 0 && parent.Hash() == chain.Config().DefaultGenesisHash {
+			return parent.Difficulty()
+		}
 		genesis := chain.GetHeaderByHash(parent.Hash())
 		genesisTotalLogS := progpow.TotalLogS(chain, genesis)
 		if genesisTotalLogS.Cmp(genesis.ParentEntropy(common.PRIME_CTX)) < 0 { // prevent negative difficulty
diff --git a/core/genesis.go b/core/genesis.go
index 4c197abc52..c1b9c8b765 100644
--- a/core/genesis.go
+++ b/core/genesis.go
@@ -274,6 +274,7 @@ func (g *Genesis) ToBlock(startingExpansionNumber uint64) *types.WorkObject {
 	head.Header().SetExtra(g.ExtraData)
 	head.Header().SetGasLimit(g.GasLimit)
 	head.Header().SetGasUsed(0)
+	head.Header().SetExpansionNumber(uint8(startingExpansionNumber))
 	if startingExpansionNumber > 0 {
 		// Fill each byte with 0xFF to set all bits to 1
 		var etxEligibleSlices common.Hash
diff --git a/core/worker.go b/core/worker.go
index a925d37f87..0caab89ca1 100644
--- a/core/worker.go
+++ b/core/worker.go
@@ -1090,7 +1090,11 @@ func (w *worker) prepareWork(genParams *generateParams, wo *types.WorkObject) (*
 		if parent.NumberU64(common.PRIME_CTX) == 0 {
 			newWo.Header().SetEfficiencyScore(0)
 			newWo.Header().SetThresholdCount(0)
-			newWo.Header().SetExpansionNumber(0)
+			// get the genesis expansion number, since in the normal expansion
+			// scenario this is only triggered in the case of [0, 0] we can just read
+			// the genesis block by number 0
+			genesisHeader := w.hc.GetBlockByNumber(0)
+			newWo.Header().SetExpansionNumber(genesisHeader.ExpansionNumber())
 		} else {
 			// compute the efficiency score at each prime block
 			efficiencyScore := w.hc.ComputeEfficiencyScore(parent)