Tuesday, April 05, 2016

Candidates Round #13




This was an intense round with three high-octane draws and one inconsequential win. Tailender Nakamura beat tailender Topalov to pull himself back to 50 per cent. But that mattered a lot less than the three draws played out by Caruana, Karjakin and Anand, A win by any member of this troika would have altered the last round dynamics.

Caruana-Svidler played a sizzler and Caruana finally flubbed a well-known technical win, albeit one that is notoriously difficult. if he had converted that position, the American would have pulled ahead.

As it happened, that 100-move-plus draw might have set things up for Karjakin, who would also have the solo lead if he beat Aronian. Only, Karjakin was under massive pressure and barely survived through another 100-mover, where he defended with his customary coolth (if one may borrow a word coined by the late Sir Terry Pratchett).

Those two games went on for a very long time. All four players looked utterly physically exhausted by the end. The draws meant that the Karjakin-Caruana clash in Rd 14 would be critical.

Meanwhile, Anand-Giri was drawn in "only" 50-odd moves but it was also an exciting game. Giri got adventurous and sacrificed a piece against Anand. It was hard to make sense of what was going on, But that also burnt out into a draw. If Anand had put this one away, he would have tied Caruana and Karjakin and had everything to play for in the last round. But with the benefit of hindsight, Anand never looked like winning.  

Let's look at the games in ascending order of complexity and importance.


This was out of a Queens Gambit Declined. Black looks much better with his dominant rooks and his well-placed Kt c4. But is he really? That white Bishop is an absolute  boss, protecting g2 and controlling h7,g6. White should activate immediately with 33. Ra1! - Now neither pawn can be taken without allowing an immediate draw 33.- Nxe5 34. Ra8+ Kf7 35. Ra7+ or 33.-- Rxb4  34. Ra8+ etc.  Black can play on with 33. Ra1 Rd8 of course but then he has nothing much with 34. Ra7 Rxb4 35. Rg3 g5 36. Bh7+ Kh8 37. Bc2 generating dangerous counterplay

Topalov was not in time trouble (he very rarely is). Nor are these variations hard to calculate. It is an indicator of his very poor form (and probably, lack of motivation by this stage) that he played  33.Rg3 Re2 34.Ra1 Nxe5 35.Ra8+ Kf7 36.Bh7 g5 37.Bg8+ Kf6 38.Rf8+ Kg7 39.Re8 Ng6 40.Bxe6 Nf4 (0–1). If 41. Bd7 Rxe8 42. Bxe8 Ne2+ kills it

Anand-Giri looked nice and equal in the diagram.
On normal moves like 24. -- Qc5 25. Bd3, it should just burn out. Instead, Giri tried the amazing 24.-- Bxf2+!?
After the more or less forced sequence 24. Bxf2+ 25.Kxf2 Qb6+ 26.Kf1 Nh5 27.g4 fxg3 28.Bd3 Rxe1+ 29.Rxe1 Nf4 30.Nd4 g6 31.Be4 Qf6 it's hard to tell who is better, if indeed anybody is. Anand returned the exchange on e1 and then sacrificed his entire queenside to pile onto f7. If Giri doesn't take the perpetual towards the end, Ng4-h6 is a potent threat from white's side. Also black must beware of white marching Kh6. But of course, Giri took the perpetual.

This game pretty much finished Anand's challenge in the event. Of course, when Anand's game ended, Aronian was pressing against Karjakin and Caruana-Svidler was unclear. But both Caruana and Karjakin would have to lose to give Anand a reasonable chance in Rd 14.

Aronian had built a nice edge out of an English Opening

 


 Crazy  tactics start at this point. Both players assessed the normal 25, -- c6 26. Rxb5 cxb5 27. Nd6 s good for white. The engines agree that this is a little superior for white. 
The actual play went 25.-- Nxa3?! 26.c6! Qe7 27.Qa2 bxc6 28.Rxc6 Bf7 29.Rc5! This hits Nd5 and cuts off the Queen's defence of the Kt-a3. It triggers the next tactical flurry. Black went with 29.-- Nxe3!? 30.Qxa3 Rxb2 31.Qxb2 Nxg2 32.Kxg2 a3 33.Qb7 Qd8 34.Qxc7 Qxc7 35.Rxc7 Bd5 36.Rc5 a2 37.Bc3 Bg8 38.Ba1 Rb8 39.Ra5 Rb1 40.Bc3 Rd1 and somehow black is still hanging on. Aronian must have thought he was winning. He tried all sorts of reshuffles and complicated piece placements over the next umpteen moves. But Karjakin just kept finding good defensive resources.

Caruana - Svidler was more up and down.



Black has generated serious pressure in the centre. He seems better because the Qd5 has more influence than Qa4. But the last move 34.. - Rae8 misses a cute little tactic. White played 35.dxe5 Nxe5 36.Nxe5 Rxe5 37.Bxf4! and now the apparently excellent 37. -- Rxe4? 38. Rxd5 Rxe1+ Kh2 39. Nxf4 is refuted by an X-ray 37. -- Rxe4? 38. Qxe8+!  and the white queen's placement suddenly makes sense. So Svidler had to play 37.-- Qb5 38.Qxb5 Rxb5 39.Bd6 Kh8 40.g4 Nf6 41.Nxf6 Rxe1+ 42.Rxe1 Bxf6 43.Re8+ Kg7 44. Bb4 Re5 45. Rc8 and white is better because he can target the queenside pawns.  But this is by no means easy to win.

Caruana  soldiered on to reach this position 


White is two pawns up but even this is probably not winning. The pure rook endgame with bishop and rook is technically drawn (though people have been known to lose it). Black keeps his rook on the h-file (as distant as possible) and rook goes to h1 and starts checking from the first rank, or the h-file  if white tries to walk in with his king. It's impossible to make progress against good defence.

The pure bishop endgame would also be drawn because the a8 queening square cannot be controlled, Black just sacrifices his bishop for the c-pawn at some stage and sits on a8 with his king. White will deliver stalemate.

So white has the job of keeping both pieces on and trying to finagle something. Black played for another known technical draw with 63.Kd3 Rh5 64.c5 Kb7 65.Rg6 Bxa5 66.Bxa5 Rxc5 and the R+B Vs Rook ending is drawn. Note that the 50-move rule has kicked in with the last capture on 66.

People, meaning a genius called Andre Danican Philidor started looking at this material set up in the 18th century. It's drawn with correct play from most situations and Philidor found several of the most critical set ups. Computer analysis gives us an exact countdown of any given set up. All five piece positions have long since been solved.

There is also the 50-move rule. This favours the defender because quite often, forced wins go over 50. For a while, this material used to be played out with a special extension to 75 moves because of that factor. But it's long since reverted to 50-moves.  

In practice, White will always push the black king to the edge of the board and guard checks against his own king by interposing bishop. But black has a choice of squares to step to with his king. Judicious retreat will hold the draw. He must also keep his rook active of course and there are also stalemate defences in some situations.

Despite centuries of study and complete solutions, this is an incredibly hard position to play, Offhand, I can recall several superGMs, such as Grischuk, Ulf Andersen and Jan Timman who have played this out and made serious errors. We can add Svidler and Caruana to that list.


Svidler has just made a terrible error with 102-.. Ka5-a4?. Instead 102.--Ka6 103. Rb1 Rc8! holds the draw because the white king can't get  "mating opposition" with Kc6. For that matter, 102. -- Rg8 or 102. Re8 holds the draw.

After 103.Kc4! Rh4+ 104.Bd4 Rh5 white could win with the Philidor method which is outlined in in any standard textbook such as Basic Chess Endings.

He can  play 105. Rb2 Rh3 (to stop Ra2#) 106. Bg3! (prevents Rh4+ and causes zugzwang) Rf3.  Pulling the rook away from the edge of the board is vital. Now white plays 107. Bc5! Rf4+ 108. Bd4 Rf3 109. Rb4+! Ka5 110 Rb7 and mates due to f6 control. (This is one reason why Rf3 needs to be forced).

Or 109. Rb4+ Ka3 110. Rb7 Ka2 111. Rb2+! Ka3 112. Re2 (Bc5+ is the deadly threat) Ka4 113. Be3! (Another reason to force Rf3) Ka3 114. Bd6+! Ka4 115. Ra2+ Ra3 116, Rxa3# In both cases, mates is within the 50-move limit.

Instead Caruana frittered the big chance away with 105.Bf2 Rg5 106.Rh7 Rg4+ 107.Bd4 Rg5 108.Rh8 Rb5 109.Ra8+ Ra5 110.Rb8 Rh5 111.Bf6 Ka5 112.Bc3+ Ka6 113.Bd4 Rh6 114.Be3 Re6 115.Rb3 Rc6+ 116.Kd5 Draw.


 So it all boiled down to the last round.








Sunday, April 03, 2016

Candidates Round #12



Well. it's all over and I'm posting late but the final three rounds of the Candidates had their fair share of excitement.  Round 12 was where the young guns pulled ahead.

Anand played awfully and lost a near miniature to Nakamura. Meanwhile Karjakin beat Topalov and Caruana fought a long battle with Aronian who missed a crazy winning idea. Giri and Svidler played a draw that lasted 85 moves without either player ever looking to have serious winning  chances. 

After Rd 12 it was clear that either Caruana or Karjakin would be favoured to win. Anand still had mathematical chances but the momentum had clearly passed to the two younger men. 

Anand's third loss in the tournament came in contrasting style to his first two losses. However, there were commonalities in that all three losses came with black, against young players, in amorphous English/ Reti systems.

There could be a hole here in terms of either opening preparation, or perhaps, comfort. These positions can sometimes be mind-numbingly quiet and boring. But they can also be blindingly sharp. Maybe Anand doesn't enjoy non-linear manoeuvring in such schizophrenic systems with their high rates of transposition.  

Against Karjakin in Rd 4, he had played an aggressive opening setup and then suddenly gone into passive mode, exchanging pieces when he should have kept the tension. Karjakin played superb technical chess thereafter.

Caruana  plain and simple, out-prepared Anand in Rd 10. The Italian-American found a stunning sacrifice in the late opening/ early middlegame. That left him with the advantage and he pushed Anand over the edge with excellent middle game play.  

Against Nakamura, Anand self-destructed through hyper-aggression. That g5 thrust was over-ambitious. The followups were just egregious errors. It's hard to imagine what Anand could have missed since the tactics just flow naturally against black's position, given the way he played.  

Nakamura is a difficult opponent for Anand due to either some sort of a psychological block, or some stylistic issues, or possibly a mix of both factors. Anand's head-to-head record against Nakamura is really bad and a game like this does seem to indicate psychological problems.




White's taken a deliberately provocative stance by "trapping" his Kt on h4. But he's got the obvious breaks d4, d3, and b4. Black can play steadily with 10..- Bb6 or 10. -- Be6
Instead lback picked 10.-- g5!? and after 11. b4 Bb6?! white is much better. He has better pawn structure with targets along the a1-h8 diagonal. Plus he has better development and a much safer king.  Black could have gone with 11. b4 gxh4! 12. bxc5 dxc5 or 12. Bb2 Nxd5 13. cxd5 Ne5 14. bxc5 Bg4 and this is unclear because black does have attacking chances here.


White's already winning. He has more space and a safe king. He has a lead in development. Sooner, rather than later, he will develop mating threats along  the long black diagonal. In contrast black has no apparent targets.

Nakamura played the strong but obvious 17.e5 hxg3 18.hxg3 Qg5 19.exd6 Rxd6 20.Qb3 h5 21.Rad1 Rh6 22.Rd5 Qe7 23.Qc4 Bg4 24.Qf4 Rg6 25.Re5 Qd6 26.Be4
(1-0). For the second time in this event( the first being versus Karjakin), Anand resigned with equal material on the board. He's losing at least an exchange since 26.-- Re6 27. Bd5 Rxe5 28. Qxf7+ Kh8 29. Be4 or 26.-- f5 27. Bxf5 Bxf5 28. Qxf5 Rf8 29. Qxh5 are both dreadful.


The Karjakin Topalov game turned into a pawn storm on opposing flanks. It was a classic open Sicilian.  Both players must mix attack and defence judiciously.


Black wants to get threats of Nxa3 going, which explains his next move which hits the Nc3. But he forgets  that white can let rip with h6. Black should play 17.-- Bf6! which gives him the option of recapturing on g7 with his Bishop. He can then carry on with 18. h6 hxg6 19. hxg7 Bxg7 and he still has a strong counter-attack  to come with Rc8. etc

The game turned here with 17. --- Rc8? 18.h6! fxg6  Unfortunately for black, 18.--Nxa3 19. gxh7+ Kxh7 20. hxg7+ Kxg7 leads to mate. One line would be 21. Rh7+ Kxh7 22. Qh5+ Kg7 23. Rg1+ etc.  Also 18. -- Bf6 is refuted by 19. hxg7 Bxg7 20. Qh5!

19.Nxe6 Qd7 20.Nxf8 Bxf8 21.hxg7 Bxg7 22.Bd4 a5 23.Bxg7 Qxg7 Karjakin plays exactly as the position requires. White is an exchange up but black has some residual chances of a counter-attack and Karjakin breaks those up convincingly.  

White's next move sets up the threat of Qe6+ and gains time for him to enhance the pressure with Qg5-h6. The very sensible dual-purpose Rh3 protects Nc3 and prepares rook doubling if required.

White won with 24.Qg4! Re8 25.Qg5 Bc6 26.Qh6 Qh8 27.b3 Nxa3 28.Rh3 Bd7 29.Rg3 Qf6 30.Rh1 Re7 31.Qh4 Qg7 32.Nd5 Rf7 33.Qd8+ Qf8 34.Qxa5 Nxc2 35.Qc3! (1-0). The threat of Rxg6+ turns the Kt sac on c2 into a joke.

Just in case, you've forgotten Karjakin had lost a long, difficult endgame to Anand in the previous round, To come out guns blazing regardless, and win a game like this is a sign of the mental strength that makes him such a feared competitor.

The Caruana - Aronian game saw a missed opportunity, which could have been the sacrifice of the tournament, maybe of the entire year, if Aronian had played it.



Both sides have been fooling around for a while in an equal position. White's last move (38. Rb1-a1) is actually a big error.

Black has the  insane 38.-- Rxd3!! 39. cxd3 Qxd3+ and if 40. Kg1 Qc4! and the pawns will roll home while the alternative 40. Ke1 Qxe4+  41. Kf1 Qd3+ 42. Ke1 Qd2+ 43. c2!    loses as does 40. Ke1 Qxe4+  41. Kd1 Qd3+ 42. Kc1 Qd2+ 43. Kb1 Qe1+ 44. Ka2 Qxf2+ 45. Kb1 Qf1+ 46. Ka2 Qxg2+ 47. Kb1 Qe4+ 48. Qc2 Qc4 with 49.-- b3 coming.   

Aronian missed this though he managed to build some pressure. They played out the ending till move 65 without either player making a significant error again.

The Svidler -Giri saw black rapidly achieve a superior position. But it was hard to make progress and Giri never came close to conversion.He did miss several tries that the engines consider superior.