The 2015 World Cup came to a madcap conclusion after six crazy tiebreak games, all of them decisive, and after a series of topsy-turvy games the last man standing was Sergey Karjakin. Both he and Peter Svidler have qualified for next year's Candidates' tournament, but it was Karjakin who secured the title of World Cup Champion and the extra $40,000 that went with it. He won $120,000 to Svidler's $80,000, and both will be able to afford some quality help as they try next year to qualify for a match with Magnus Carlsen.
The tiebreak match was every bit as crazy as the classical match (or rather, the classical portion of the match). Both players won must-win games, and knowing what happened in the preceding game or even who came out of the opening better off told one almost nothing about what would happen by the game's end. Let's give a quick recap of the games.
In game 1 (game 5 overall), the first of the 25' + 10" contests, Karjakin had White and played an unusual line of the English. He may have obtained a slight edge at first, but Svidler outplayed him and managed to achieve all his strategic aims. Perhaps he was never quite winning, but he was much better for a very long time. He was never in danger until he missed 42.Ng4, and even then things weren't so bad for a while. Finally, though, they reached an opposite-colored bishop ending where Karjakin didn't seem to have any real winning chances, but he managed to make progress. He was a little careless about it and gave Svidler three chances to find a blow that would have put Karjakin on his heels trying to find the draw, but finally White put a stop to the idea. After 79 moves the last critical moment of the game appeared. Karjakin had made as much progress as he possibly could "for free", while Svidler was at his last line of defense. Unfortunately for him, Karjakin had, and found, 80.d5!!, and that won the game.
Svidler had lost three games in a row by this point, one he was winning outright (game 3) and one (this one, game 5 overall) where he was much better for a very long time. Now it was his turn to have to win to stay in the match, and despite all the discouragement he must have felt by this point he came through in spades, winning a remarkably clean game with White in a King's Indian Attack. Somehow the Svidler of the first two and 9/10 games had returned, and it was match on once again.
Games 3 and 4 of the tiebreak (7 & 8 overall) were with the 10' + 10" time control, and this time Karjakin faltered with White. His attempt to avoid an inferior sort of Modern Benoni led to something worse, and things just snowballed from there. Karjakin was already losing when he played 23.Rxc4?, but that cost him a piece to an elementary tactic. The game went on a while longer, probably so Karjakin could get mentally prepared for the next game, but there was never any doubt as to the result over the course of the remaining moves.
So once again Svidler had White in a game where he only needed to draw, and once again...he failed to score. He chose a differet anti-Sicilian line than he did in game 3, but here too it wound up in a sort of Maroczy Bind. Karjakin apparently surprised him somewhere, because Svidler played hesitatingly and then overreacted and overreached on the queenside. After 15 moves Svidler was losing a pawn, after 23 moves he was losing a second pawn, and after 27 moves he resigned. A disaster for Svidler, but good nerves by Karjakin, who had saved his third "match point".
On to the blitz: 5' + 3". Yet again Karjakin started with the white pieces, and this time there was something new. Karjakin played 1.e4 for a change, and Svidler headed for his beloved Marshall. Karjakin went all the way into the rabbit hole, but even though they went into a main line he was somehow unprepared and played a terrible novelty on move 18, Bc2. Svidler had plenty of time, having gained almost 40 seconds on the clock by this point, and he used two or three minutes trying to figure out what to do against this new move. It's clear from his facial expressions that he figured it out...a few seconds after making the wrong move. Black could have played 18...Nxc3, with a decisive advantage. A less tired Svidler would have spotted this (for that matter, a less tired Karjakin probably would have seen it as well before playing 18.Bc2), but instead he played 18...b4, which was a bad move in its own right in addition to missing a huge opportunity. A few moves later Karjakin could have been winning, but even with his imprecise 24th move he maintained a significant advantage.
Unfortunately for Svidler, his horrors had not yet come to an end. Bit by bit he fought back, only to make a serious error on move 28. Karjakin could have replied to 28...Bh5 with 29.g4, with a winning advantage, but instead he played 29.Rb1??, allowing several winning rejoinders. Svidler's wasn't the best, but it was good enough for a winning advantage. Once again it was time for Karjakin to demonstrate his resilience, and while Svidler maintained his advantage over the next dozen or so moves he didn't make much progress. He did have an advantage on the clock, but having more time and more material won't rescue you when you blunder a rook, as he did. He simply left his rook en prise on b8, Karjakin took it, and Svidler's anguish was palpable. You will rarely see a player more distraught than Svidler was, but there was still another game to play, one more chance for a comeback.
With White Svidler managed to achieve a serious, possibly winning advantage. This time around there weren't any blunders that gave the game away; it was just the slow but steady drip of inaccuracies that allowed Karjakin to equalize, and at the end even win when Svidler was forced to gamble to avoid a draw. Svidler found a very nice trick at the end of the game that could have won, but Karjakin found the right response and Svidler had to resign. A very bitter end for Svidler, who was winning or nearly winning in games 3, 5, 9 and 10 and lost them all.
So Karjakin won the tiebreak 4-2 and the match by the overall score of 6-4. (The games are here, with my comments.) Incredibly, both players are headed to Berlin at the end of the week for the World Rapid & Blitz Championships. They might be so tired by now that I would stand a decent chance against them, but hopefully they will recover well enough to play near enough to full strength to avoid a catastrophe. One final note about the event. At the end of the press conference Sergey Karjakin mentioned that he had been given some advice by Sarkhan Gashimov, the brother of the late super-GM Vugar Gashimov and a talented chess player in his own right. He also recounted his friendship with Vugar and that the dying Vugar had told him that from now on he, Karjakin, had to play for the both of them. It was a moving moment and a nice gesture to the Azeris, as Gashimov was one of their own. We shall see next March whether he, or Svidler, can take a further step towards the world championship when the Candidates' tournament takes place.