It was another day full of fight and craziness in Dortmund, and in the end the chase pack drew closer to the leader, Liviu-Dieter Nisipeanu. Nisipeanu gave up his first half point in the event, but although he had White it was his opponent, Hou Yifan, who had whatever winning chances there were. The key moment was Black's 21st move. If Hou wanted to play for a win she'd have to make go pawn-snatching, taking either on b2 or a2. Both moves seemed to be alright, but with White's pieces clustering around her king she took a practical decision that more or less forced a perpetual check some moves later.
That was a good result for both players, in different ways, and it benefited the rest of the field too as it brought the leader back to the pack. The first player to exploit this was Arkadij Naiditsch, who won his second game of the tournament with Black (sandwiching a loss with White!). The victim this time was Wesley So, who got in trouble in several stages. First, allowing 18...d4 gave Black tremendous activity. It wasn't fatal though, and probably didn't even promise Black any advantage, but it made the position more challenging for White - especially against a dangerous attacker like Naiditsch. Second, 21.Ra1 was a clear error, ceding the c-file. So had to do something about the threat of 21...Rxc1 followed by 22...Qe1+ 23.Rxe1 Rxe1#, and 21.Ra1 fulfilled that task. It would have been better to play 21.g3, however, taking care of the back rank without conceding the file. There was an exchange of errors on move 24 (I'm guessing that both players missed 24...Nf4 25.Qh6 Qf6!, threatening especially 26...Bf8), and the final, now fatal, error came on move 26 when White grabbed the a-pawn. White is still kicking after 26.Qf3, though Black will have the upper hand. After 26.Qxa6? the rest was a massacre, and Naiditsch finished in style.
That put Naiditsch at 2/3, and he was joined there by Vladimir Kramnik. Kramnik beat Ian Nepomniachtchi with some tactical confusion. Kramnik had a significant advantage out of the opening but when it slipped away around move 25 the game remained equal through the time control. Kramnik did maintain an initiative, however, and with his rook and knights hopping around the Black king Nepo needed to stay on high alert. Black's fatal error was 46...Be5, when 47.Nb7 (with the idea of 48.Nd8 and 49.Rf7#!). While Black was able to stop that threat, there were too many other threats that he couldn't, and Kramnik soon reached a completely winning knight ending.
Finally, Georg Meier let a full point slip away against Fabiano Caruana. Meier was winning and then some, right up until the time control. By then it was equal while remaining complicated, and Meier didn't manage to retain the balance. A tough loss for him; he could quite easily have had 2.5/3 by now.
Here are the round pairings:
- Caruana (1.5) - Naiditisch (2)
- Hou Yifan (1) - So (1)
- Nepomniachtchi (1) - Nisipeanu (2.5)
- Meier (1) - Kramnik (2)