If you play 1.e4 and see Black answer 2...Nc6 followed by 3...b6, you have already won the opening battle. After 1.e4 c5 2.Nf3 Nc6 3.d4 b6 4.d5, Stockfish evaluates the position at +1.90, a clear advantage for White. Across over 107,000 games, White scores a crushing 62.5% win rate with only 3.2% draws — meaning Black is fighting for survival from move four. The interactive drill below lets you practice converting this advantage against the engine.
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Play the Sicilian Defense: Open: b6 against the engine
Free, no signup — you play white, the engine adapts to your level.
Play the interactive drill below to practise converting White's near-winning advantage in the Sicilian Open b6. Test yourself against the engine and see if you.
Find your own #1 mistake — free →Why 3...b6 Is a Gift to White
The Sicilian Defense is built on fighting for the d4-square and keeping the position imbalanced. Black's move 3...b6 in this line abandons those goals. Instead of developing a piece or challenging the centre, Black fianchettoes a bishop that will immediately be blocked by White's next move. After 4.d5, Black's knight on c6 must move, and the bishop on b7 is staring at a brick wall. White has gained space, time, and a target — everything you want from an opening. The statistics back this up: a massive +1.90 evaluation means you have a near-winning edge. That is a huge advantage for you, so trust the position and look for the most active continuation.
The Engine's Top Reply: Black's Knight Runs
Faced with 4.d5, Black's best try is to retreat the knight to a5. This is played in over 38,700 games — by far the most popular choice — and the engine confirms it is the only move that does not worsen an already bad situation. The full engine line runs 4...Na5 5.e5 a6 6.Nc3. Notice how White simply keeps pushing: e5 gains more space in the centre, Nc3 develops a piece, and Black is reduced to pushing pawns on the queenside. Even in Black's best line, White scores 58.7% from this position. That is an excellent winning rate, and you achieve it by following simple developing moves and not overreaching.
The Blunders Black Plays Most Often
The statistics reveal that many Black players crack under the pressure of 4.d5. Two of the most common replies — 4...Nb8 (25,510 games) and 4...Nd4 (13,940 games) — are labelled as inaccuracies, costing roughly 0.5 and 0.8 pawns respectively. Worse is 4...Ne5, played in 1,655 games, which is a full blunder that loses about 3.3 pawns compared to the best move. White scores an eye-popping 81.1% against 4...Ne5 and 80.1% against 4...Bb7. When your opponent makes a mistake like this, your task is simple: develop quickly, keep the centre strong, and don't let them organise counterplay. The engine will show you the most punishing replies.
How to Handle Each Popular Reply
If Black plays 4...Na5 (the best move), your plan is 5.e5 a6 6.Nc3 — gain space and develop. Black's knight is awkwardly placed on the rim. If Black plays 4...Nb4, the stats are even better for you: White scores 66.1%. The knight on b4 looks active but can become a target. If Black blunders with 4...Ne5, you can win material by attacking the knight immediately — White wins over four out of five games from that position. Against 4...Bb7, White's score of 80.1% shows you can simply capture or advance and enjoy a huge space advantage. The common thread: you have the centre, you have space, and Black is scrambling. Trust your advantage and choose the most active, principled move.
Results across 107,150 Lichess games
| Most-played continuation | Games | White wins | |
|---|---|---|---|
| 1 | Na5Main line | 38,766 | 58.7% |
| 2 | Nb4 | 25,662 | 66.1% |
| 3 | Nb8 | 25,510 | 60.4% |
| 4 | Nd4 | 13,940 | 65.9% |
| 5 | Ne5 | 1,655 | 81.2% |
| 6 | Bb7 | 587 | 80.1% |
Frequently asked questions
Is the Sicilian Defense Open b6 line good for Black?
No. After 1.e4 c5 2.Nf3 Nc6 3.d4 b6 4.d5, Stockfish evaluates the position at +1.90 in White's favour — a near-winning advantage. Black's idea of fianchettoing on b7 is easily thwarted by White's central push.
What is Black's best move after 4.d5 in this Sicilian line?
The engine recommends 4...Na5, retreating the knight to the edge of the board. From there the main line continues 5.e5 a6 6.Nc3. Even in Black's best line, White scores 58.7% across almost 39,000 games.
What are the common mistakes Black makes in the Sicilian Open b6?
Black's 4...Ne5 is a blunder costing roughly 3.3 pawns, while 4...Nb8 and 4...Nd4 are inaccuracies. White wins over 80% of games after 4...Ne5, and over 65% after 4...Nd4. The best move by far is 4...Na5.
Why does the b6 Sicilian variation give White such a big advantage?
Black's 3...b6 prepares a bishop on b7, but White's immediate 4.d5 blocks that bishop and forces Black's knight to move again. White gains space, time, and a lead in development — three key advantages that add up to a near-winning edge.
How many games feature the Sicilian Defense: Open: b6?
Over 107K Lichess games have reached the Sicilian Defense: Open: b6 position. White wins 62.5%, Black wins 34.3%, with 3.2% draws — based on real rated games.