Arkadij Naiditsch vs Haochen Jiang: game review

12.d4! The only good move here: every alternative is clearly worse.

• Shores up the e5 pawn, which was under as much attack as it had defence (3 against 1).
• Takes e5 away from the Black queen on c7.
• The next best move, 12.Bb2, would drop White's winning chances from 59% to 40% (−1.14).
• 12.d4 stops …Ncxe5.
• Black was threatening …Ncxe5, winning a pawn. d4 takes care of it.
• Black answers 12…d5.

26…Qf5! The only good move here: every alternative is clearly worse.

• Moves the attacked queen to safety.
• Lines up queen and bishop on the diagonal, so the two pieces push in the same direction.
• The next best move, 26…Bxg4, would drop Black's winning chances from 49% to 29% (+2.49).
• 26…Qf5 threatens …Qxh5, winning the queen, and gets the queen out of the way of gxf4.
• It threatens …Qxh5, winning the queen, so White has to spend the next move on it.
• White was threatening gxf4, winning the queen for a pawn. The queen steps away.

34.Ba2 is a blunder: White's winning chances go from 48% to 22%.

• Black answers 34…Be5: adds a attacker on the knight on d4: 2 attackers against 2 defenders.
• Better was 34.Nb3 (−0.20), which attacks the queen.

Better: 34.Nb3 threatens Nxc5, winning the queen for a rook, and stops …f4. Engine line: 34…Qd6 35.Ne3 Qe7 36.Nd5 Qd8 37.Nxc7 Qxc7 38.Nc5 (−0.20).

42…e3!! A real sacrifice: Black gives up material and the engine still rates it best.

• Leaves the knight on d7 where it can be taken.
• Taking is too dangerous: White's best reply is 43.Qd3 Qxd3 44.Nxd3 e2 instead (the engine rates it −6.53).
• A pawn break: it challenges the f2 pawn to open lines.
• 42…e3 stops Qxd7 and threatens …Nc5, winning a pawn, picking it up with 44…exf2.
• White was threatening Qxd7, winning a knight and a pawn. e3 takes care of it.
• It threatens …Nc5, winning a pawn, picking it up with 44…exf2, so White has to spend the next move on it.

• The idea: 42…e3!! leaves the knight on d7 hanging. Taking it gives Black the material back and more.
• What Black gives up: The knight on d7 is attacked by the queen on d1, and 42…e3 doesn't save it. That's a knight on offer.
• If White takes the knight: 43.Qxd7 is met by 43…exf2+, taking the f2 pawn with check. Then 44…Qxg3 takes the g3 pawn, and 45…Qg1+ gives check. Black ends up a piece ahead: Black is winning (−11.77).
• White's best try: White's best is to leave the knight alone and play 43.Qd3. Black answers 43…Qxd3, taking the queen on d3 and threatening …exf2+, winning a pawn. Then 44…e2 creates a passed pawn on e2, and 45…a6 pushes the passed pawn to a6. Black ends up two pawns ahead: Black is winning (−6.53).

• Both sides followed opening theory up to 4…Qb6: 8 moves in all, 4 by White and 4 by Black.
• Theory runs out after 4…Qb6: too few games between strong players reached this position to go further.