Chessy
Sicilian Defense: O'Kelly Variation, Yerevan System for White
After 1.e4 c5 2.Nf3 a6 3.Nc3, you reach a flexible Sicilian where Black has chosen an unusual move order. Your task as White is simple: keep the centre strong, develop naturally, and be ready for Black’s most common replies. The position is already a little easier for White, so this drill helps you turn a small edge into a real opening advantage without memorising long lines.
Play the Sicilian Defense: O'Kelly Variation, Yerevan System against the engine
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Create a free account →What the engine says about this position
Stockfish rates this +0.31, a small edge for White. That means you are slightly better here.
The engine’s best move for Black is e6, continuing e6 d4 cxd4 Nxd4. In other words, Black is aiming for a solid, active Sicilian setup and will usually try to challenge your centre soon. Your job is to stay accurate and not let Black equalise comfortably.
The most common replies you need to know
This position has been reached in 587,780 games, so there is a lot of practical experience behind it. The most-played continuations are Nc6, e6, d6, b5, g6, and h6.
The numbers are close, which tells you this is a playable opening for both sides. Still, White’s results are a little better overall, so if you know the ideas behind the position, you can ask Black real questions instead of drifting into a quiet equal game.
What White should focus on
This structure rewards straightforward opening principles. You want to claim space in the centre, develop your pieces to useful squares, and keep your king safe.
Because Black has already played a6, you should be alert to queenside ideas and flexible pawn play. At the same time, do not rush—this is a position where good development and central control matter more than forcing tactics.
The one mistake to punish
One known mistake here is g6. It loses about 1.2 pawns, and the better move was e6.
That is useful for your drill: if Black chooses g6, you should understand that the move is strategically and tactically loose compared with the engine’s preferred setup. Even when the position looks calm, small inaccuracies can swing the evaluation quickly.
Results across 587,780 Lichess games
| Most-played continuation | Games | White wins |
|---|---|---|
| Nc6 | 181,889 | 47.4% |
| e6 | 178,465 | 46.0% |
| d6 | 93,618 | 45.2% |
| b5 | 85,894 | 46.3% |
| g6 | 17,071 | 48.6% |
| h6 | 11,733 | 49.0% |
Frequently asked questions
Is the Sicilian Defense: O'Kelly Variation, Yerevan System good for White?
White has a small edge here. Stockfish gives +0.31, and the database results are also slightly in White’s favour overall. That makes this a good position to learn if you want practical chances without needing a sharp gambit.
What is Black’s best move in this position?
The engine’s best move is e6, and it continues e6 d4 cxd4 Nxd4. That shows Black is looking for a solid Sicilian development scheme rather than immediate tactics. In your drill, you should be ready to meet that structure cleanly.
Which replies are most common after 1.e4 c5 2.Nf3 a6 3.Nc3?
The most-played continuations are Nc6, e6, d6, b5, g6, and h6. Since several moves are popular, you need a flexible plan rather than one narrow memorised line. The drill helps you get used to each of these setups.
What should I do if Black plays g6 here?
g6 is a known mistake and loses about 1.2 pawns. The better move was e6. If you face g6 in practice, you should recognise that Black has given you a chance to take the initiative.
How many games feature the Sicilian Defense: O'Kelly Variation, Yerevan System?
Over 587K Lichess games have reached the Sicilian Defense: O'Kelly Variation, Yerevan System position. White wins 46.7%, Black wins 49.6%, with 3.8% draws — based on real rated games.