The 2010 US Chess Championship is taking place from May 13 (round one at 2:00 p.m. local time) to May 25 (possible tie breakers) at the Chess Club & Scholastic Center of Saint Louis, which is hosting the event for the second year in a row. The prize fund has risen to $170,000 – more than a 25 percent increase from last year. The winner will take home $35,000.

Round six results

The round featured three Grunfeld Defenses. Despite relatively good results for Black in the first five rounds, White won six of the eight decisive games in round six. This is the third round which featured eight winners. Overall, the championship has had a draw rate so far of 39 percent, up slightly from 2009, which was 34 percent.

An uneventful draw between the pre-round leaders and two decisive games on boards two and three have landed GM Gata Kamsky, GM Alex Onischuk, GM Hikaru Nakamura and GM Yury Shulman atop the tables with 4.5/6. The four players, which comprised 80 percent of the last U.S. Olympiad Team, are all undefeated with three wins and three draws each.

Onischuk and Kamsky played for the fourth time in their careers and the result went the way of the previous three. Nakamura, entering the round for the first time not in first place, caught back up with an endgame swindle against GM Jesse Kraai. Nakamura fell behind on the clock for one of the first games in the event and became worried that Kraai’s celerity meant some home cooking. “I didn’t want to walk into anything,” Nakamura said.

Also winning to tie for the lead was Shulman, who beat GM Alex Stripunsky. Like Nakamura, Shulman won a rook-and-pawn endgame due to his more active rook.

GM Varuzhan Akobian, the fifth member of the Olympiad team, could not join the leaders. He played the longest game of the round but was unable to win with his extra pawn, despite GM Larry Christiansen’s claim that “Armenians have great endgame technique.” In one of the most studied endgames, GM Alex Yermolinsky was up to the task and held the draw without too much difficulty.

Another unlikely player doing well also had a slip in round six. IM Irina Krush lost to Christiansen. While her chances of making the quad are gone, she still has a lot to play for. With two out of her last three she will earn a grandmaster norm and she even has good chances with only 1.5 out of three.

Standings after six rounds

With the four players at 4.5 and Christiansen at 4, a group of players at 3.5 will need to win and some luck. That list includes GM Alex Shabalov, who defeated GM Gregory Kaidanov, GM Ben Finegold, who defeated GM Joel Benjamin, Akobian, Stripunsky and Yermolinsky.

The pivotal round seven match-ups include Shulman-Onischuk on board one, Christiansen-Nakamura on board two, Kamsky-Shabalov on board three, Kraai-Stripunsky on board four, Yermolinksy-Finegold on board five and Hess-Akobian on board six. Only one of these players will control his own destiny, as he will play someone in the 4.5 score group. Not everyone with 4.5 can be paired with each other for round seven since there have been too many head-to-head matchups already.

“I’ve reached a similar situation to last year where I’ve played everyone at the top,” Nakamura said. “I’ve been the wrong colors against the wrong people.” Nakamura seemed resigned to bad pairing luck going forward. “I’m pretty much expecting the worst,” he said.

Report by FM Mike Klein, photos by Betsy Dynako

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