diff --git a/core/blockchain.go b/core/blockchain.go
index 927e4628df..5cf917e7ec 100644
--- a/core/blockchain.go
+++ b/core/blockchain.go
@@ -1774,10 +1774,10 @@ func (bc *BlockChain) insertChain(chain types.Blocks, verifySeals bool) (int, []
 	return 0, events, coalescedLogs, nil
 }
 
-func (bc *BlockChain) InsertBlock(block *types.Block) error {
+func (bc *BlockChain) InsertBlock(block *types.Block) (int, error) {
 	events, logs, err := bc.insertBlock(block)
 	bc.PostChainEvents(events, logs)
-	return err
+	return 0, err
 }
 
 func (bc *BlockChain) PrepareBlock(block *types.Block) (err error) {
diff --git a/eth/fetcher/block_fetcher.go b/eth/fetcher/block_fetcher.go
index 6ad600ff69..3f32f24eb3 100644
--- a/eth/fetcher/block_fetcher.go
+++ b/eth/fetcher/block_fetcher.go
@@ -93,6 +93,9 @@ type chainHeightFn func() uint64
 // chainInsertFn is a callback type to insert a batch of blocks into the local chain.
 type chainInsertFn func(types.Blocks) (int, error)
 
+// blockInsertFn is a callback type to insert a batch of blocks into the local chain.
+type blockInsertFn func(types.Block) (int, error)
+
 type blockPrepareFn func(block *types.Block) error
 
 // peerDropFn is a callback type for dropping a peer detected as malicious.
@@ -166,9 +169,10 @@ type BlockFetcher struct {
 	handleProposedBlock proposeBlockHandlerFn // Consensus v2 specific: Hanle new proposed block
 	broadcastBlock      blockBroadcasterFn    // Broadcasts a block to connected peers
 	chainHeight         chainHeightFn         // Retrieves the current chain's height
-	insertChain         chainInsertFn         // Injects a batch of blocks into the chain
-	prepareBlock        blockPrepareFn
-	dropPeer            peerDropFn // Drops a peer for misbehaving
+	// insertChain         chainInsertFn         // Injects a batch of blocks into the chain
+	insertBlock  blockInsertFn // Injects a batch of blocks into the chain
+	prepareBlock blockPrepareFn
+	dropPeer     peerDropFn // Drops a peer for misbehaving
 
 	// Testing hooks
 	announceChangeHook func(common.Hash, bool) // Method to call upon adding or deleting a hash from the blockAnnounce list
@@ -211,7 +215,7 @@ type BlockFetcher struct {
 // 		dropPeer:            dropPeer,
 // NewBlockFetcher creates a block fetcher to retrieve blocks based on hash announcements.
 
-func NewBlockFetcher(getBlock blockRetrievalFn, verifyHeader headerVerifierFn, handleProposedBlock proposeBlockHandlerFn, broadcastBlock blockBroadcasterFn, chainHeight chainHeightFn, insertChain chainInsertFn, prepareBlock blockPrepareFn, dropPeer peerDropFn) *BlockFetcher {
+func NewBlockFetcher(getBlock blockRetrievalFn, verifyHeader headerVerifierFn, handleProposedBlock proposeBlockHandlerFn, broadcastBlock blockBroadcasterFn, chainHeight chainHeightFn, insertBlock blockInsertFn, prepareBlock blockPrepareFn, dropPeer peerDropFn) *BlockFetcher {
 	knownBlocks, _ := lru.NewARC(blockLimit)
 	return &BlockFetcher{
 		notify:              make(chan *blockAnnounce),
@@ -234,9 +238,10 @@ func NewBlockFetcher(getBlock blockRetrievalFn, verifyHeader headerVerifierFn, h
 		handleProposedBlock: handleProposedBlock,
 		broadcastBlock:      broadcastBlock,
 		chainHeight:         chainHeight,
-		insertChain:         insertChain,
-		prepareBlock:        prepareBlock,
-		dropPeer:            dropPeer,
+		insertBlock:         insertBlock,
+		// insertChain:         insertChain,
+		prepareBlock: prepareBlock,
+		dropPeer:     dropPeer,
 	}
 }
 
@@ -772,7 +777,7 @@ func (f *BlockFetcher) insert(peer string, block *types.Block) {
 			return
 		}
 		// Run the actual import and log any issues
-		if _, err := f.insertChain(types.Blocks{block}); err != nil {
+		if _, err := f.insertBlock(*block); err != nil {
 			log.Warn("Propagated block import failed", "peer", peer, "number", block.Number(), "hash", hash, "err", err)
 			return
 		}
diff --git a/eth/handler.go b/eth/handler.go
index af823c62e1..3739b11c58 100644
--- a/eth/handler.go
+++ b/eth/handler.go
@@ -246,7 +246,7 @@ func NewProtocolManager(config *params.ChainConfig, mode downloader.SyncMode, ne
 		return blockchain.CurrentBlock().NumberU64()
 	}
 
-	inserter := func(blocks types.Blocks) (int, error) {
+	inserter := func(block types.Block) (int, error) {
 		// If sync hasn't reached the checkpoint yet, deny importing weird blocks.
 		//
 		// Ideally we would also compare the head block's timestamp and similarly reject
@@ -254,7 +254,7 @@ func NewProtocolManager(config *params.ChainConfig, mode downloader.SyncMode, ne
 		// case when starting new networks, where the genesis might be ancient (0 unix)
 		// which would prevent full nodes from accepting it.
 		if manager.blockchain.CurrentBlock().NumberU64() < manager.checkpointNumber {
-			log.Warn("Unsynced yet, discarded propagated block", "number", blocks[0].Number(), "hash", blocks[0].Hash())
+			log.Warn("Unsynced yet, discarded propagated block", "number", block.Number(), "hash", block.Hash())
 			return 0, nil
 		}
 		// If fast sync is running, deny importing weird blocks. This is a problematic
@@ -263,10 +263,11 @@ func NewProtocolManager(config *params.ChainConfig, mode downloader.SyncMode, ne
 		// out a way yet where nodes can decide unilaterally whether the network is new
 		// or not. This should be fixed if we figure out a solution.
 		if atomic.LoadUint32(&manager.fastSync) == 1 {
-			log.Warn("Fast syncing, discarded propagated block", "number", blocks[0].Number(), "hash", blocks[0].Hash())
+			log.Warn("Fast syncing, discarded propagated block", "number", block.Number(), "hash", block.Hash())
 			return 0, nil
 		}
-		n, err := manager.blockchain.InsertChain(blocks)
+		n, err := manager.blockchain.InsertBlock(&block)
+		// n, err := manager.blockchain.InsertChain(blocks)
 		if err == nil {
 			atomic.StoreUint32(&manager.acceptTxs, 1) // Mark initial sync done on any fetcher import
 		}