We didn’t manage to post an update of the odds after round 6, but not much changed. Carlsen remained around 53% to win the Sinquefield Cup, Aronian remained around 17% to win. Nakamura’s win and Topalov’s loss caused them to swap places, with Nakamura improving to 15% from 4%, and taking over as the third most likely victor, and Topalov dropping to just 3% from almost 17% before the round. It was just minor shuffling though, for the most part little changed in round 6.
Not so in round 7, where there was a drastic shakeup at the top! Carlsen and Aronian entered the round tied, and the odds heavily favored Carlsen going forward by virtue of his much higher rating, but instead round 7 shocked the standings when Carlsen lost to Grischuk and Aronian defeated Nakamura in the same day. Suddenly Aronian emerged with a full point lead and just two rounds left to play, making him now a huge favorite to win the event!
As for the Grand Chess Tour, things were actually the other way around. Round 6, while somewhat uneventful for the odds of the Sinquefield Cup, had a huge impact in the GCT odds. Topalov’s loss mattered a lot there, dropping him to just 41% to win the tour, down from 63% before the round. The big gainers were Carlsen (who improved to 27% from 20% by drawing and remaining tied for the lead) and Nakamura (who improved to 19% from under 7% with his win).
However when Nakamura and Carlsen both lost in round 7, those gains were wiped away. Aronian climbed slightly higher than we’d seen, now up to a 6% chance of winning the tour title, but having finished second-to-last in Norway he remains a long shot even if he wins here in St. Louis. Here is where the full field now stands: