diff --git a/consensus/beacon/consensus.go b/consensus/beacon/consensus.go
index b594bf3b04..d64b125c72 100644
--- a/consensus/beacon/consensus.go
+++ b/consensus/beacon/consensus.go
@@ -235,6 +235,12 @@ func (beacon *Beacon) verifyHeader(chain consensus.ChainHeaderReader, header, pa
 	if len(header.Extra) > int(params.MaximumExtraDataSize) {
 		return fmt.Errorf("extra-data longer than 32 bytes (%d)", len(header.Extra))
 	}
+	// Validate Optimism extraData format
+	if chain.Config().IsOptimism() {
+		if err := eip1559.ValidateOptimismExtraData(chain.Config(), header.Time, header.Extra); err != nil {
+			return fmt.Errorf("invalid optimism extraData: %w", err)
+		}
+	}
 	// Verify the seal parts. Ensure the nonce and uncle hash are the expected value.
 	if header.Nonce != beaconNonce {
 		return errInvalidNonce
diff --git a/ethclient/ethclient_test.go b/ethclient/ethclient_test.go
index f98829967e..2acd384aa6 100644
--- a/ethclient/ethclient_test.go
+++ b/ethclient/ethclient_test.go
@@ -238,7 +238,6 @@ func newTestBackend(t *testing.T, config *node.Config, enableHistoricalState boo
 func generateTestChain(genesis *core.Genesis, length int) []*types.Block {
 	generate := func(i int, g *core.BlockGen) {
 		g.OffsetTime(5)
-		g.SetExtra([]byte("test"))
 		if i == 1 {
 			// Test transactions are included in block #2.
 			if genesis.Config.Optimism != nil && genesis.Config.IsBedrock(big.NewInt(1)) {