The Sicilian Defense: McDonnell Attack with g6 — How to Play It as White

By playing 2...g6, Black signals a hypermodern approach: they plan to fianchetto the bishop to g7 and control the centre from the flank. Your f2-f4 pawn push has given you a broad centre, but it also weakened the e1-h4 diagonal slightly and committed the f-pawn. Black's bishop on g7 will eye the d4 and e5 squares, making it hard for you to advance without preparation. Your job is to build a pawn centre with c3 and d4 before Black can undermine it. The engine's favourite continuation — Bg7 c3 Nc6 d4 — shows exactly this: you clamp the centre while developing naturally. If Black avoids Bg7, they risk falling behind in development or leaving the kingside dark-squared bishop awkwardly placed.

The most-played reply in the database — 3...Bg7 with 343,852 games — is also the engine's top choice. It's the principled move: Black completes the fianchetto and keeps all options open. Against Bg7, White scores 46.9%, which is right around the statistical average for the position. Your plan is simple: c3, then d4, then develop naturally. The two moves the engine flags as inaccuracies are 3...e6 and 3...Nf6. Both lose roughly 0.8 pawns compared to Bg7. The problem with e6 is that Black blocks the light-squared bishop and leaves the dark-squared bishop stuck behind the pawn chain — the g7 fianchetto is much more active. Nf6 attacks e4, but after your natural c3 and d4, the knight can become a target rather than a threat.

If you look at the database numbers, you'll notice something interesting: White's winning percentage is actually lowest against the best move. Against 3...Bg7 (the engine's first choice), White scores just 46.9% — slightly below the overall average. Against 3...d6 (only 18,532 games), White scores 50.7%, your best result among the common replies. And against 3...Nf6 (a mistake), White jumps to 54.6% — a huge swing. This tells you that most of your advantage comes from Black misplaying the position, not from a forced refutation. Be patient. If Black plays accurately with Bg7, you reach a roughly equal middlegame where your space in the centre (pawns on e4, f4, and eventually d4) gives you easy development and attacking chances on the kingside. Let Black make the first mistake.

Once you've played c3 and d4 (after Black's Bg7), the typical structure looks like: White pawns on e4, d4, f4, and f3 if needed; Black pawns on d6 or e6 with a fianchettoed bishop on g7. Your plan is to attack on the kingside using the f-pawn as a battering ram. Advancing f5 can open lines against Black's king, who will often castle short behind that g7 bishop. Meanwhile, Black will try to strike back in the centre with ...d5 or ...e5, or play on the queenside with ...b5 and ...Nc6-a5. This is not a quiet positional opening — it's sharp, with both sides having clear trumps. The engine says it's dead equal, so the better tactician wins. Use the drill to practise the first moves and get a feel for the resulting middle-game positions.