Candidate moves II

In this second part of my article about Candidate Moves, we will have a look at some situations where you have many moves to choose from. Let's start with a very simple case.

Black to play. He is a piece down, but we can sense a back rank motif. We quickly discard 1...Nc6 and 1...Nf5 due to 2.Re1. Also bad is 1...Nf3+ 2.gxf3 or 1...Ne2+ 2.Kf1!. Neither does 1...Nxc2 work due to 2.Nxc2 Rd1+ 3.Re1. But 1...Nb3 turns out to be strong. White then has to give back some of the material by 2.Re1! Nxa1 3.Be3, and after 3...Nxc2 4.Nxc2 he is slightly better in the endgame. What am I trying to say here? That Black has to scan carefully all the knight moves, in order to find 1...Nb3!, his best and only choice.

Now let's see a much more complex case, with a similar pattern.

Black to move. Just like in the previous position, any black knight move generates a lethal threat, in this case ...Bd6-c5 winning the white queen. So when looking for candidate moves, it is natural to focus on the moves with this knight. Also we should notice that if the white queen leaves d4, Black could take on g5 without being mated. A good starting point is 1...Nxe4. After 2.Nxe4 Black can reach an ending by 2...Bc5 3.Nxc5 Qxc5. But White has the bishop pair, and a pawn for the exchange, so he should be safe. Let´s see if there is something better. 1...Na4 allows 2.Rxe8 with the point 2..Bc5? 3.Rxf8+ Kxf8 4.Ne6+. We also have the flashy 1...Nb3. What should White do here? It seems that 2.Bxb3! Bc5 3.Ne6 leads to a level game, despite the material imbalance, e.g. 3...Rxe6 4.Rxe6 Qxf4?! 5.Qxc5 bxc5 6.Rf1. The bishop pair gives White stability in all these lines. Any knight move left? Yes, one. The modest retreat 1...Nd7. Only one threat here, 2...Bc5, but what can White do against it? For example, 2.Kh1 Bc5 followed by 3...fxg5, or 2.Ne6 Rxe6 followed by 3...Bc5. Finally, if 2.Rxe8 then 2...Bc5! 3.Rxf8 Nxf8 (this recapture is a main point behind 1...Nd7) 4.Ne4 Bxd4+ 5.Bxd4 Qxc4 and White is in serious trouble due to his loose pieces.

In the game, Black went for the tempting 1...Nb3?! and Korobov was later able to save a draw, thus avoiding a major tournament upset. No blame on Druska - the "modest" 1...Nd7! is not easy at all to decide upon.

On other occasions, the candidate moves are harder to find. Sometimes, we have to widen our focus from the main battlefield towards other zones of the board, in order to make the right choice. Here is an example.

White to play. In exchange for the minus pawn, we have a strong attack. We quickly spot several candidate moves here: 1.Nxh6+, 1.Qg6+, even 1.Nxf6+ followed by 2.Qg6+ or 1.Bxf6 followed by 2.Qg6+. However, if you start analyzing them, you will soon see that White won´t get more than a pawn in these lines. There is a much stronger move. Check carefully the rest of the board! You'll see... 1.f3. Thus White mobilizes his rook, with devastating effect. Even 1.f4!? is possible, but 1.f3! is more clear-cut, eliminating the defender on e4. In the game, the Brazilian GM replied 1...fxe5, and apparently resigned before his lesser known opponent effected 2.fxe4 Qg7 3.Nxh6+ followed by 4.Rf7, or the fancy 3.Rf7!?, in both cases with an immediate win.

Hats off to the young Uzbek player, not even an IM, who needed only 4 (four) seconds to play 1.f3!.

Here is last, more complex case.

White to play. Black has just played ...Qd1-d3, trying to swap queens in order to repel the enemy attack. How to react with White? Our first impulse might be the intermediate check 1.Qa8+. But after 1...Kh7, we can´t play 2.fxe5? due to 2...Bxe5+, and 2.Ne6 Ng6 3.Bxg7? runs into 3...Qe3 and Black prevails. 1.Qd5 has a better aspect to it, e.g. 1...Nc4 2.Qf7! with 3.Ne6 next. However, while checking 1.Qa8+ we already noticed that White's king is exposed too, so (after 1.Qd5) the trick 1...Ng4+! is no real surprise for us. There follows 2.hxg4 Bxf4+ 3.Kg1 Qe3+! 4.Kf1 Qd3+ with a perpetual, as 5.Ke1?? Bg3 is mate. Finally, in the ending arising after 1.Qxd3 Nxd3 Black has no reason to be worse, e.g. 2.g3 Kg8 3.Nf5 Bf8. Any other square available for the queen? Yes, McShane found the neat 1.Qf5! and now taking on f5 leads to the loss of the g7-pawn, thus Agdestein tried the tricky 1...Qe3. Again White has many options. 2.fxe5? Bxe5+ 3.Kh1 Qc1+ is curtains. 2.Ne6 looks natural, but 2...Nf3+! is a cold shower. White must accept a draw after 3.gxf3 Qf2+, since 3.Kg3?? Nd4+ drops the queen. 2.Nb5? runs into the same 2...Nf3+!, and after 3.gxf3 Bxf4+ Black even wins. However, don´t forget the backward moves! McShane played 2.Nc2!, seeing that 2...Nf3+ can now be met by 3.Kg3! when 3...Nd4+ fails to 4.Nxe3 Nxf5 5.Nxf5. Thus Agdestein had to rely on 2...Qf2, but after 3.Bxe5 Bxe5 4.Qc8+! followed by 5.fxe5 White won a piece and soon escaped the queen checks.

Very precise play by McShane, and even more impressive if you consider that this was a rapid game.

I hope you have enjoyed these examples! Here are a few related exercises.

1. White to play. (4-5 moves)
_____________________________

2. White to play. (3-4 moves)
_____________________________

3. White to play. (2-3 moves)
_____________________________

4. Black to play. (4-5 moves)
_____________________________

And here are the solutions to the exercises in the previous post (Candidate moves) :
1. Seeing 1...Bf8? 2.Ne7+ Kg7 3.Nf5+ followed by 4.Nxh6+ and 5.Qxf7+, Black must prefer 1...Kh7 (rejection logics), and after 2.Qxf7 Qh3+ 3.Kf2 Qh2+ 4.Kf1 Qh3+ 5.Ke1 Qg3+ 6.Kd2 Qd6 he is alive.
2. Only 1...Qa6! intending 2...R(Q)c8 saves Black. Then after 2.Qxc7 Nd2 (or 2...Nxe3) he is OK.
3. Black's only move is 1...Kg7! avoiding the intermediate checks on e7/e8. Then after 2.d7 Rd8, 2.Re7+ Kf6 or 2.Rd5 Ra8, he can fight for a draw.