Okay, this is getting ridiculous. For the fourth time in five days, Hikaru Nakamura emerged victorious in San Sebastian. And now he's doing it with both colors. He outplayed San Segundo in a sharp line of the Cambridge Springs QGD with 9..e5, an offbeat move that didn't catch on after Smyslov lost with it against Kasparov in their 1984 candidates match. That moved the American to a spectacular 4.5/5 and a full-point lead with four rounds to play. Top seed Svidler moved up in the standings to +2 with his second straight win, adding to Karpov's woes.
Always a "show me" player, Nakamura grabbed a pawn on a3 instead of Smyslov's retreat with 10..Bd6. White gets space, the bishop pair, and some initiative for the pawn, but 14.cxd4 looks a little funky. It gave Black two connected passers instead of just the passed a-pawn. Black kept improving, though it looked like it was going to be a very long slog to mobilize the pawns when San Segundo made things very hard for himself by letting the queens come off. He achieved an opposite-colored bishops position but with knights still on the board no blockade would work. 32..Rc4! is the sort of petite tactic that typifies Nakamura's games. The unexpected stabs and jabs keep coming in the service of an overall strengthening of the position.
San Segundo hung tough and put up enough resistance to give himself drawing chances thanks to those mismatched bishops and some inaccuracies by Nakamura. After 47.Nb6 it's not clear how Black is going to make progress. The white d-pawn is dangerous and the a-pawn is locked down. But once again Nakamura handled the complications better than his opponent and two weak moves were enough to return White to the critical list. Allowing a fork to remove his bishop removed many of the drawing possibilities. 51.Nf5 Be4 52.Ne3 was still a fight, it seems. Black allowed no second chances and finished cleanly.
An incredible run, but the tournament's not quite over yet. Nakamura has white tomorrow against one of his two closest pursuers, Ponomariov. He's already faced the other, Svidler, both on +2. Nobody else is even in the picture for the top spot, which is rather unusual. Svidler made beating the Petroff look easy today with the nice Nimzowitschian clearance sac 15.e6! Karpov defended quite well at first and a computer probably would have been happy with the black position even after the ominous 19.g5. But the veteran just can't handle these sharp positions these days and he went downhill fast. The wheels completely came off the Karpov ZIL with 30..c6? and 31..g4?, though it was probably already over. As fun as it is watching Nakamura's star shine so brightly in Donostia this past week, it's pretty painful seeing Karpov ripped up so badly. I knew it was going to be bad, but not this bad. Let's hope for a consolation win for him in the final four rounds.
Did Vallejo really play 1.e4 c5 2.Nc3 a6 3.g4?!? against Vachier-Lagrave as the official site and score say? This comes a few days after I received the latest NIC Yearbook and its article on "White playing g4 against just about everything." But this? I would believe it was a typo and that he played the usual 3.g3 except for one thing. On move 24 (until then there as no real difference) Black could have played the strong 24..f5 if the pawn had been on g3 instead of g4. (Also ..f5 on move 25.) Wild. Granda-Movsesian was a congested King's Indian with a nominal advantage for White he couldn't exploit. Ponomariov was pushed back in his Catalan by Kasimjanov in an interesting game that ended too soon.
Round 6: Nakamura-Ponomariov, Svidler-Vallejo, Vachier-Lagrave-San Segundo, Kasimjanov-Granda, Karpov-Movsesian.
If Nakamura wins again just invoke the softball slaughter rule and hand him the trophy. Not to get ahead of things, but even if he doesn't win another game Nakamura could start the event barely in the top 30 on the rating list and finish it tantalizingly close to the top dozen.