Playing the Grob Opening: d6 as White

White's setup with 1.g4 and 2.Bg2 aims to fianchetto the bishop on the long diagonal. The g4-pawn stakes a claim on the kingside and prepares to push h2-h4, gaining space. However, the move g4 weakens the squares f4 and h4, and does nothing to control the centre with pawns on d4 or e4. Black's two main ideas are either to challenge the g4-pawn directly (with a move like ...Bxg4) or to develop solidly and exploit White's lag in central control. The engine's top line is Nc6, simply developing a piece and threatening nothing immediately — which shows that Black can afford to play calmly and trust their slight long-term edge.

From the position after 1.g4 d6 2.Bg2, Black has six commonly seen moves. Let's look at the most important ones by frequency and by what they mean for you as White. The most-played reply overall is Nc6 (37,171 games), but White only scores 45.2% against it. That is your toughest test. The engine also recommends Nc6 as the best move, so expect a principled opponent to head here. The second most popular is c6 (34,542 games), where White scores a bit better at 48.1% — but we know from the statistics that c6 is actually an inaccuracy that loses about 0.6 pawns compared to Nc6. That small edge is worth knowing about.

The statistics flag three concrete mistakes Black can make in this exact position. The most severe is Bxg4 — snatching the gambit pawn. It is played 29,976 times and White scores a crushing 57.7% against it. The engine confirms Bxg4 is a mistake losing about 1.8 pawns. Black takes the bait but falls behind in development and leaves the kingside vulnerable after you recapture. Next is Nf6 (23,577 games, White scores 53.4%). This develops sensibly but loses about 1.1 pawns; Black blocks the f-pawn and allows you to chase the knight with h2-h3 and later g4-g5. Finally, c6 (34,542 games) is only an inaccuracy, not a full mistake, but White still scores a respectable 48.1%. Your task is straightforward: when Black grabs the g4-pawn or misplaces a knight, you convert that advantage.

The engine's best continuation after 2.Bg2 runs Nc6 h3 h5 gxh5. White plays h3 to defend g4, Black pushes h5 to break the pawn chain, and White captures. The resulting position leaves White with an extra h-pawn but a weakened kingside and Black's pieces are active. This is the main theoretical line you should be comfortable with. If Black plays c6 instead of Nc6, you can be confident you are already slightly better than in the main line. And if Black plays Bxg4, you simply recapture and enjoy a large advantage. In the drill, the engine will test you against all these moves.