Denis Makhnev vs Daniil Dubov: game review

17…Nd4!! A real sacrifice: Black gives up material and the engine still rates it best.

• Puts the knight on d4 where it can be taken.
• Taking is too dangerous: White's best reply is 18.c3 Nxb3 19.axb3 Rfd8 instead (the engine rates it −0.37).
• 17…Nd4 prepares …Nxb3 and …Rfd8.
• The engine's plan continues with …Nxb3 and …Rfd8: this move is the first step.
• The knight on d4 can be taken by the rook on d1.
• White answers 18.c3, attacking the knight on d4, which is undefended.

• The idea: 17…Nd4!! offers the knight on d4. Taking it gives Black the material back and more.
• What Black gives up: 17…Nd4 puts the knight on d4 where it can be taken by the rook on d1. That's a knight on offer.
• What it does instead: It threatens …Nxc4, winning a pawn.
• If White takes the knight: 18.Rxd4 is met by 18…Nf3+. Then 19…Nxd4 takes the rook on d4, and 20…Nxb3 takes the bishop on b3. Black ends up two pawns ahead: Black is winning (−4.25).
• White's best try: White's best is to leave the knight alone and play 18.c3. Black answers 18…Nxb3, taking the bishop on b3 and threatening …Nxa1, winning a rook. Then 19…Rfd8 threatens …Rxd1+, winning a rook, and 20…Rxd1+ gives check. Material is level and Black holds the balance (−0.37).

57.Rh4 is a mistake: White's winning chances go from 28% to 16%.

• Black answers 57…Ra2: the rook reaches the seventh rank, where 2 pawns sit.
• After Ra2, Black wins 1 point of material within 4 moves.
• Better was 57.Kd2 (−2.59).

Better: 57.Kd2 prepares Rb3 and cxd4+. Engine line: 57…d4 58.Rb3 Ra4 59.cxd4+ Rxd4+ 60.Ke2 (−2.59).

57…Ra2! The only good move here: every alternative is clearly worse.

• The rook reaches the seventh rank, where 2 pawns sit.
• Attacks the b2 pawn, which is undefended.
• The next best move, 57…Kd6, would drop Black's winning chances from 84% to 74% (−2.82).
• 57…Ra2 wins a pawn, picking it up with 58…Rxb2.
• Sets up a sequence and wins a pawn once the captures settle, picking it up with 58…Rxb2.
• White answers 58.Ke3.

• Both sides followed opening theory up to 5…O-O: 10 moves in all, 5 by White and 5 by Black.
• White left the book with 6.e5. In 100 games from this position, strong players played 6.O-O (76%), 6.Bb3 (11%) or 6.Qe2 (9%).
• The main line goes on 6.O-O Nxe4 7.Nxe4 d5 8.Bd3 dxe4 9.Bxe4 Nd7 10.c3 c5.
• From here White scored 47% in those games, with 7% drawn.