The World Cup has reached the quarter-finals and the fatigue is starting to show. With no rest days other than those earned by avoiding tiebreaks, the players have been playing for most of the past 13 days. Caruana and Vachier-Lagrave have managed to get three days off; Kramnik, Kamsky, Tomashevsky two; Svidler, Andreikin and Korobov just one. That's not easy, especially as there aren't any tension-free games.
The nerves and fatigue have been showing, as I said, and that in almost all of today's games. Tomashevsky-Kamsky was a 16-move draw, and while Kamsky had equalized it seems likely that part of the story was that Tomashevsky simply didn't have the emotional energy to force himself to go for a big fight. His tournament road has been absolutely exhausting: he escaped the first round by winning an Armageddon game, and after a relatively straightforward win in normal time in round 2 he came up against Aronian. He came through that test, and then went through yesterday's incredible tiebreak with Morozevich, needing to win in 169 moves with Black just to force more playoff games. It's a pity to burn a white game so quickly, but self-preservation is part of the game here.
Andreikin-Svidler was the one game where it seemed to me that nerves and exhaustion didn't play much of a role. Andreikin played a Torre Attack-cum-London System, and was on the verge of making progress when Svidler found the excellent idea of 19...f6, 20...Rae8 and 21...e5. The tactics made it work by a single tempo, and Svidler soon found himself with an edge. He was satisfied with a draw though, believing that the sort of small advantage he had wasn't the kind that would plausibly lead to a win.
The other draw saw Vachier-Lagrave really pushing against Caruana, and at some points Vachier-Lagrave thought it was or was about to be technically winning. He made a few inaccuracies though, and Caruana just managed to escape and draw a pawn-down ending.
Finally, there was one win. Kramnik defeated Korobov with White, alternating stretches of good play with serious errors. He was winning or very nearly so in the early middlegame, but 29.Rb7? was a big error, allowing Black to the opportunity to round up and take White's powerful passed c-pawn. 29.Rd7 would have stopped that, and then the win would have been more straightforward. Korobov was in time trouble though, and his plan of 32...g6 followed by the exchange sac 33...Rxc6 gave Kramnik a winning advantage all over again. (32...Ne7 and grabbing the c-pawn without sacrificing anything would have led to a position where Kramnik's compensation was sufficient, but not more - or at worst not much more.) Still, prosperity didn't seem to suit the ex-champion, and he missed the relatively obvious 38.Qb4, just about winning on the spot. Fortunately for him his advantage was too large to squander, and he converted the win in the second time control.
Kamsky, Caruana, Korobov and Svidler have White tomorrow (Saturday) - stay tuned.