7th Winterthur 
Combinations from the Winterthur Chess Week 2006 —
solutions
Position 1:
FM Hansruedi Glauser — WGM Anna Zozulia
How could black win this position immediately (this oppurtunity went unnoticed and the game eventually ended in a draw)?
Zozulia played 24...Qh8 here, after which the game quickly ended in a draw (½-½ on move 38).
Instead, the "exchange" 24...Rh1:! would have been very strong, for it deflects the white rook from his duties to protect the square d3, thus allowing after 25.Rh1: the fork 25...Nd3+. Therefore the move 24...Rh1: would have won at least a rook.
Position 2:
WGM Alyona Goreskul — Urs Leuenberger
Here, the Ukrainian grandmaster Alyona Goreskul found a beautiful combination. Do you spot it too?
The weakened black back rank and the white lead in development (look at black's queenside!) allow the deadly blow 1. Nd5: as the following variations prove:
(A) 1... cd: 2. Qd5:! White's queen is immune due to the mate on e8 and the double attack on black's queen and knight will leave white with a plus of two pawns.
(B) 1... Be6 2. Qb7: is winning for white.
(C) The game continued 1... Nd7 2. Ne7+ Kf8 3. Ng6+!. Now the knight cannot be taken because of 3... fg: 5. Bg6: and after the moves 3... Kg8 4. Re7 black did well to resign.
Position 3:
Reto Wyss — Norbert Barz
On his last move, white allowed the black fork 15. ...Nd5xc3 with the idea of sacrificing his bishop with 16.Bc4xf7+. Comment on the game, that went 16. ...Kg8xf7 17. Qe2-c4+ Nc3-d5 18. Nf3-g5+ Kf7-f6 19. Nd2-e4+ (1-0) and find an improvement for black.
The critical position arises after the moves 16. Bf7:+ Kf7: 17. Qc4+ Nd5 18. Ng5+ cf. the analysis diagram on the right.
Perhaps black has chosen his next move here by using the method of elimination: "18... Kf8 fails due to the fork 19.Ne6+ and after 18... Kg8 the move 19. Ne6 also wins my queen; so the only possibility is 18... Kf6, that protects the important e6 square. Alright, I have to play 18... Kf6."
This fictious line of thought clearly shows the advantages and disadvantages of the method of elimination: advantage — one can save time and energy, because there is no need to calculate every variation behind the forced and only move as there is no choice anyway; disadvantage — one runs the risk to reject a good move in order to play a bad variation without any deep analysis.
Here, a second look on the position reveals: the seemingly only move 18...Kf6 leads, as the game shows, to a quick mate and the apparent loss of the queen after 18...Kg8 19.Ne6 is everything but inevitable:
18... Kg8! 19. Ne6 b5!
This Zwischenzug was probably overlooked by black. If white now removes his queen from the attack, so black can do the same, as now the squares a5 and b6 are freed.
20. Nd8: bc: 21. Nb7: cd: 22. ed: Bd4:
Black now possesses a strong (extra) passed pawn and white's knight will have a hard time finding a way back to the game. In a higher sense, white's position is lost. It might follow:
23. Nf3 Bb6! 24. Rfc1 c3 25. Rb3 Ra8 26. a4 Ra7 27. a5 Rb7: 28. ab: Rb6: -+
Position 4:
Andreas Lehmann — GM Vadim Malakhatko
White just moved 21. Bb2-e5 and suprisingly resigned on seeing his opponent's reply. Do you see the reason for Lehmann's sudden resignation?
Black moved 21... Qb6! decisively pinning the white rook on e3. If white now had protected this rook by 22. Rfe1 black would have the strong 22...Ne5:! 23. fe: Bg5 winning the exchange.
Position 5:
Zoltan Zambo — IM Branko Filipovic
Find the wrong move for white!
Positionally speaking the move 1. Rf2? makes some sense. But it certainly does not pass the tactical tests: after 1... Rc3:! white resigned.
Position 6:
WGM Alyona Goreskul — Paul Remensberger
Find the wrong move for black!
In view of white's strong pressure on the queenside, black would be very happy to exchange queens. But if black moves his knight, for instance to e4, then he is mated in one by 2. Nb6#. That's why in the game the move 1...Nc4? was played, in order to protect the mate on b6. But after 2.Qc4:! Black resigned, as he cannot take on c4 due to the aforementioned mate.
