Both of today's matches were exciting battles, with comebacks, surprising twists, and in which the winner's identity was unclear almost to the very end.
First up, Levon Aronian vs. Alexander Grischuk. Aronian started off with a pair of wins, but no matter: Grischuk struck back with two wins of his own. Game 5 was drawn, and then things started to get weird. Grischuk was winning in game 6 but let it slip, but then Aronian made a remarkable blunder with more than enough time on his clock. Grischuk won and took a 3.5-2.5 lead, and when he achieved a winning advantage in game 7 it looked like he was on the way to an impressive comeback win. Nothing doing--he lost that game, and then collapsed. Aronian won a miniature in game 8 to take the lead, and won game 9 after a misjudged exchange sac by Grischuk to win the match, 5.5-3.5.
The match between Wesley So and Maxime Vachier-Lagrave was a drama in three acts. The first four games comprised the first act. All four games were drawn, but So missed more opportunities - especially in game 2, where he was winning on multiple occasions and for a while enjoyed an advantage so great that Vachier-Lagrave's failure to resign was almost incredible.
Act 2 was the low point for So. He had healthy though not decisive advantages in both games 5 and 6, but lost both games. With MVL up 4-2, things looked grim for the American. But then it was time for the third act...
Game 7 was headed for a draw. So was a pawn up, but in a very drawish rook ending. For a long time MVL held, but eventually his vigilance slipped and So managed to win. And with that, everything changed. In game 8 So obtained the advantage early on, and kept it, winning a good technical game. In game 9 the Frenchman blundered in an equal position, and game 10 was...mostly a massacre. (See the analysis for details.) So won the last four games to finish with a 6-4 match victory.
In normal events, the schedule would suggest that So would play Aronian in one semi-final, but that's not how things work here. So will play the winner of tomorrow's match between Fabiano Caruana and Le Quang Liem, while Aronian will play Magnus Carlsen. (Or Anish Giri, in case Carlsen dies or his ISP is hit by a meteorite. C'mon, Anish, prove me wrong!)
Here are some of the games, mostly from the Aronian-Grischuk match, with brief comments. (Event website here.)