The 2018 Sinquefield Cup, the final qualification leg of the Grand Chess Tour, is a nine-round tournament from August 17-28. At the end of the tournament, four players will qualify for the London finals. The games in St. Louis begin at 1 p.m. Central U.S. time daily (8 p.m. Central Europe).
"Considering the position, this was a great result," Caruana said. He'll need a few of those days to repair some newfound issues with one of his main defenses as black, the Petroff.
Even fellow players unwittingly took part. One by one, like lapped race cars moving to the apron to allow the leaders to pass, the other four outlying games all ended drawn. Carlsen (4.0/7) and Caruana (4.5/7) had the room to themselves, but the champ said he couldn't trust his normally reliable intuition.
"A lot was at stake today; I was a bit nervous," Carlsen said after the afternoon ended.
Taking white and trailing Caruana by a half point in the standings, the world champion got a sizable edge against the challenger's now-trusty Petroff. His mounting pressure caused the American to play very precisely in limited space. After the first slip-up, all of Caruana's kingside pieces huddled for warmth.
Carlsen felt so confident in his position that he made a rare visit to the confessional booth. Note that he didn't actually "confess" anything. Carlsen didn't even utter a word. How to show confidence in the most laconic way possible?
About the game, Carlsen said that while he made a specific mistake, that it was not a one-off this tournament.
"First I was slightly better then he missed this Ng4, f6 trick," Carlsen said. "Then I felt that I was close to winning, but I miscalculated. My intuition told me to go f6 before Ng4." Alas, he inverted those moves, explaining that he didn't originally see how to "refute" 27... Nf6 if he had played 27. f6 first.
All of these lines became possible because Caruana thought the f-pawn couldn't even advance to f5, let alone f6. He had planned to answer the discovered attack on his rook by taking the h-pawn.
"As soon as he took on h6, I realized that there's Ng4 and I can resign now," Caruana said, adding that a little earlier he thought he was just fine from what he understood about the position.
"It felt like it must be winning. I was absolutely sure I was winning," Carlsen said, adding that once Caruana balled up with 28...Ng8, he already couldn't find anything convincing.
"The problem is, in all my games, I'm not being practical. I just can't make up my mind, can't follow my intuition and make decisions."
All four other games ended drawn, so Caruana maintained his half-point lead over the chase group.
The most interesting of the other draws was Sergey Karjakin's attempt to get his first win. Eventually, all of the play collapsed onto the queenside, and Shakhriyar Mamedyarov held.
The game followed another big clash from the exact same room: Dominguez-Kasparov from last year's Saint Louis Rapid & Blitz.
Maxime Vachier-Lagrave got a noticeable advantage against Hikaru Nakamura, but yet another American held today. (For completeness, Wesley So was nominally down a pawn in the ending to Levon Aronian, but he held down the host country's barracks, too.)
The Frenchman got the two bishops nearly for free, but couldn't grab the win.
In the final game, Viswanathan Anand drew Alexander Grischuk in a very quiet Giouco Piano that was the first to finish.