Alexander Donchenko vs Moritz Weishaeutel: game review

20.Qf3! The only good move here: every alternative is clearly worse.

• Attacks the b7 pawn, which is undefended.
• Shores up the knight on c3, which was under as much attack as it had defence (2 against 1).
• The next best move, 20.O-O, would drop White's winning chances from 78% to 52% (+0.21).
• 20.Qf3 stops …Bxc3+.
• Black was threatening …Bxc3+, winning the queen for a rook. Qf3 takes care of it.
• Black answers 20…b5, attacking the bishop on c4, which is undefended.

22.axb4! The only good move here: every alternative is clearly worse.

• Takes the pawn on b4.
• Moving away uncovers the rook on a2, which now hits the queen on a5.
• The next best move, 22.Kf1, would drop White's winning chances from 79% to 50% (+0.03).
• 22.axb4 threatens bxa5, winning the queen, and stops …bxc3.
• It threatens bxa5, winning the queen, so Black has to spend the next move on it.
• Black was threatening …bxc3, winning a knight for a pawn. axb4 takes care of it.

23…Qb5 misses 23…Qxd5, which wins material. Black's winning chances go from 22% to 8%.

• White answers 24.Ra5, which attacks the queen.
• Better was 23…Qxd5 (+3.45), which takes the bishop on d5.

Better: 23…Qxd5 wins a bishop for a pawn and trades off the attacked queen instead of losing it to Rxa5. After 24.Qxd5 Rxd5 25.Rxa7 Rd3 26.Rc7 Re8+, the queens come off and Black comes out two pawns up (+3.45).

24.Rd2 misses the chance 23…Qb5 gave: 24.Ra5 would have punished it. White's winning chances go from 92% to 83%.

• Black answers 24…Rde8+: the rook takes the open e-file, aiming at the king.
• Better was 24.Ra5 (+6.79), which attacks the queen.

Better: 24.Ra5 threatens Rxb5, winning the queen. Engine line: 24…Rfe8+ 25.Kd1 Qb6 26.Kc2 Re7 27.Rd1 (+6.79).

26.Qd3! The only good move here: every alternative is clearly worse.

• Lines up queen and rook on the d-file, so the two pieces push in the same direction.
• The queen aims at the h7 pawn, a weak point in front of the Black king.
• The next best move, 26.Qf5, would drop White's winning chances from 91% to 54% (+0.47).
• 26.Qd3 stops …Re7+.
• Black was threatening …Re7+, winning a rook, picking it up with 27…Qxd2. Qd3 takes care of it.
• Black answers 26…Re8+, joining the attack on the king.

• Both sides followed opening theory up to 7…Be7: 14 moves in all, 7 by White and 7 by Black.
• Theory runs out after 7…Be7: too few games between strong players reached this position to go further.