Good plans have no enemy like sloppy calculation.
Goliak White
Gilburt Black
USSR Club Championship 1976
Scotch Gambit Declined C44
1 e4 e5 2 ♘f3 ♘c6 3 d4 exd4 4 c3 d5 5 exd5 ♕xd5 6 cxd4 ♗g4 7 ♗e2 0-0-0 8 ♘c3 ♗b4 9 0-0 ♕a5 10 ♗e3
Now 10...♗xc3 11 bxc3 ♕xc3 is risky after 12 ♖c1. For example, 12...♕a3 13 ♘e5 ♗xe2 14 ♕xe2 ♘xe5 15 dxe5 and ♕g4(+).
10...♘ge7 11 ♘a4 ♘f5 12 a3!
12...♗e7!
Black’s strong plan is to target the d4-pawn. Wrong would be 12...♗d6 13 ♗d2! ♕d5 14 ♘c3. For example, 14...♕e6 15 d5 and 14...♕a5 15 b4.
13 b4?
White tries to pursue two plans – attacking the queenside and harassing the Black queen. But just one is better: 13 ♗d2 ♕d5 14 ♘c3! and 15 d5.
13...♕d5 14 ♖c1
Black’s plan succeeds after 14 ♘c3 ♕e6! and ...♘xe3 or ...♗xf3/...♘cxd4.
14...♕d7??
The d-pawn would fall after 14...♕e6!, e.g. 15 ♗c4 ♕f6. Or 15 ♘g5? ♗xe2 16 ♘xe6 ♗xd1 17 ♘xd8 ♗xa4.
15 b5! ♗xf3 16 ♗xf3 ♘cxd4 17 b6!
This is what Black missed: now 17...axb6 18 ♘xb6+!.
17...♘xf3+ 18 ♕xf3 resigns.
In view of 18...♕xa4 19 ♖xc7+ and ♕xb7 mate.
Question 261: Why not 18...♗d6 19 bxa7 ♕xa4 20 ♕xf5+ ♖d7 ?
Jose Pinto White
Francisco Trois Black
Recife 1970
1 e4 e5 2 ♘f3 ♘c6 3 d4 exd4 4 c3 d5 5 exd5 ♕xd5 6 cxd4 ♗g4 7 ♗e2 0-0-0 8 ♘c3 ♗b4 9 0-0 ♕d7 10 ♕a4 ♘ge7 11 d5!? ♘xd5 12 ♘xd5 ♕xd5 13 a3! ♗d7 14 axb4 ♘d4 15 ♕d1 ♘xe2+ 16 ♕xe2 ♗b5 17 ♕e1 ♗xf1 18 ♕xf1 ♕d1? 19 ♗e3 ♕xf1+ 20 ♔xf1 a6 21 b5! axb5 22 ♘e5! resigns.