diff --git a/etherman/etherman.go b/etherman/etherman.go
index 9935805545..eb09d6601a 100644
--- a/etherman/etherman.go
+++ b/etherman/etherman.go
@@ -44,11 +44,6 @@ import (
 	"golang.org/x/crypto/sha3"
 )
 
-const (
-	// ETrogUpgradeVersion is the version of the LxLy upgrade
-	ETrogUpgradeVersion = 2
-)
-
 var (
 	// Events RollupManager
 	setBatchFeeSignatureHash                       = crypto.Keccak256Hash([]byte("SetBatchFee(uint256)"))
@@ -370,20 +365,17 @@ func (etherMan *Client) VerifyGenBlockNumber(ctx context.Context, genBlockNumber
 
 // GetL1BlockUpgradeLxLy It returns the block genesis for LxLy before genesisBlock or error
 func (etherMan *Client) GetL1BlockUpgradeLxLy(ctx context.Context, genesisBlock uint64) (uint64, error) {
-	it, err := etherMan.RollupManager.FilterInitialized(&bind.FilterOpts{
+	it, err := etherMan.GlobalExitRootManager.FilterUpdateL1InfoTree(&bind.FilterOpts{
 		Start:   1,
 		End:     &genesisBlock,
 		Context: ctx,
-	})
+	}, nil, nil)
 	if err != nil {
 		return uint64(0), err
 	}
 	for it.Next() {
-		log.Debugf("BlockNumber: %d Topics:Initialized(%d)", it.Event.Raw.BlockNumber, it.Event.Version)
-		if it.Event.Version == ETrogUpgradeVersion { // 2 is ETROG (LxLy upgrade)
-			log.Infof("LxLy upgrade found at blockNumber: %d", it.Event.Raw.BlockNumber)
-			return it.Event.Raw.BlockNumber, nil
-		}
+		log.Debugf("BlockNumber: %d Topics:L1InfoTree", it.Event.Raw.BlockNumber)
+		return it.Event.Raw.BlockNumber, nil
 	}
 	return uint64(0), ErrNotFound
 }
diff --git a/state/genesis.go b/state/genesis.go
index 60a7bcba92..47a5c6f2db 100644
--- a/state/genesis.go
+++ b/state/genesis.go
@@ -17,6 +17,11 @@ import (
 	"github.com/jackc/pgx/v4"
 )
 
+const (
+	// AutoDiscoverRollupManagerBlockNumber is the value to auto-discover the RollupManager creation block number
+	AutoDiscoverRollupManagerBlockNumber = uint64(0)
+)
+
 // Genesis contains the information to populate state on creation
 type Genesis struct {
 	// RollupBlockNumber is the block number where the polygonZKEVM smc was deployed on L1
diff --git a/synchronizer/synchronizer.go b/synchronizer/synchronizer.go
index 343f1746a1..796f019169 100644
--- a/synchronizer/synchronizer.go
+++ b/synchronizer/synchronizer.go
@@ -294,20 +294,21 @@ func (s *ClientSynchronizer) isGenesisProcessed(ctx context.Context, dbTx pgx.Tx
 // bool -> need to process blocks
 // uint64 -> first block to synchronize
 // error -> error
-// 1. First try to get last block on DB, if there are could be fully synced or pending blocks
-// 2. If DB is empty the LxLy upgrade block as starting point
+// 1. Check last synced block on DB, if there are any could be fully synced (>=genesis) or syncing pre-genesis events (<genesis)
+// 2. If no block DB then get the LxLy upgrade block as starting point for pre-genesis or use the genesis block as starting point
 func (s *ClientSynchronizer) getStartingL1Block(ctx context.Context, genesisBlockNumber, rollupManagerBlockNumber uint64, dbTx pgx.Tx) (bool, uint64, error) {
 	lastBlock, err := s.state.GetLastBlock(ctx, dbTx)
 	if err != nil && errors.Is(err, state.ErrStateNotSynchronized) {
 		// No block on DB
 		upgradeLxLyBlockNumber := rollupManagerBlockNumber
-		if upgradeLxLyBlockNumber == 0 {
+		if upgradeLxLyBlockNumber == state.AutoDiscoverRollupManagerBlockNumber {
 			upgradeLxLyBlockNumber, err = s.etherMan.GetL1BlockUpgradeLxLy(ctx, genesisBlockNumber)
 			if err != nil && errors.Is(err, etherman.ErrNotFound) {
 				log.Infof("sync pregenesis: LxLy upgrade not detected before genesis block %d, it'll be sync as usual. Nothing to do yet", genesisBlockNumber)
 				return false, 0, nil
 			} else if err != nil {
-				log.Errorf("sync pregenesis: error getting LxLy upgrade block. Error: %v", err)
+				log.Errorf("sync pre-genesis: error getting LxLy upgrade block. Maybe your provider doesnt support eth_getLogs big block range,"+
+					".Suggestion:  inform the field rollupManagerCreationBlockNumber in genesis file to avoid auto-discover. Error: %v", err)
 				return false, 0, err
 			}
 		}
diff --git a/synchronizer/synchronizer_test.go b/synchronizer/synchronizer_test.go
index ab07607398..18ffed0468 100644
--- a/synchronizer/synchronizer_test.go
+++ b/synchronizer/synchronizer_test.go
@@ -2,6 +2,7 @@ package synchronizer
 
 import (
 	context "context"
+	"fmt"
 	"math"
 	"math/big"
 	"testing"
@@ -44,6 +45,41 @@ type mocks struct {
 	//EventLog     *eventLogMock
 }
 
+func TestGetStartingL1BlockAutodiscover(t *testing.T) {
+	genesis, cfg, m := setupGenericTest(t)
+	ethermanForL1 := []syncinterfaces.EthermanFullInterface{m.Etherman}
+	syncInterface, err := NewSynchronizer(false, m.Etherman, ethermanForL1, m.State, m.Pool, m.EthTxManager, m.ZKEVMClient, m.zkEVMClientEthereumCompatible, nil, *genesis, *cfg, false)
+	require.NoError(t, err)
+	sync, ok := syncInterface.(*ClientSynchronizer)
+	require.True(t, ok)
+	ctx := context.TODO()
+	t.Run("getStartingL1Block autodiscover OK", func(t *testing.T) {
+		m.State.EXPECT().GetLastBlock(ctx, nil).Return(nil, state.ErrStateNotSynchronized).Once()
+		m.Etherman.EXPECT().GetL1BlockUpgradeLxLy(mock.Anything, mock.Anything).Return(uint64(100), nil).Once()
+		needProcess, firstBlock, err := sync.getStartingL1Block(ctx, 123, 0, nil)
+		require.NoError(t, err)
+		require.True(t, needProcess)
+		require.Equal(t, uint64(100), firstBlock)
+	})
+
+	t.Run("getStartingL1Block autodiscover Fails", func(t *testing.T) {
+		m.State.EXPECT().GetLastBlock(ctx, nil).Return(nil, state.ErrStateNotSynchronized).Once()
+		m.Etherman.EXPECT().GetL1BlockUpgradeLxLy(mock.Anything, mock.Anything).Return(uint64(0), fmt.Errorf("error")).Once()
+		_, _, err = sync.getStartingL1Block(ctx, 123, 0, nil)
+		require.Error(t, err)
+	})
+
+	t.Run("getStartingL1Block have already started sync", func(t *testing.T) {
+		m.State.EXPECT().GetLastBlock(ctx, nil).Return(&state.Block{BlockNumber: 100}, nil).Once()
+
+		needProcess, firstBlock, err := sync.getStartingL1Block(ctx, 123, 0, nil)
+		require.NoError(t, err)
+		require.True(t, needProcess)
+		require.Equal(t, uint64(101), firstBlock)
+	})
+
+}
+
 // Feature #2220 and  #2239: Optimize Trusted state synchronization
 //
 //	this Check partially point 2: Use previous batch stored in memory to avoid getting from database