On the first day of round four we saw four draws and four decisive games. With half the field pushed to the brink of elimination, it was reasonable to expect to see four players knocked out of the tournament today. And that is exactly what happened, but it wasn’t quite all four of the ones you might have thought.
Three of yesterday’s victors, Nakamura, Svidler, and local favorite Mamedyarov, did convert today, drawing their games to clinch berths in the quarterfinal round. This of course means that two of the top three seeds, Topalov and Caruana, failed to mount comebacks and are now gone from the tournament! Also eliminated, although less shockingly, was Michael Adams. What about the fourth player who won yesterday, though? Ding Liren fought hard against Wei Yi, but his 16 year old ultimately managed to find a way to win today and even the score. The two Chinese players will now have to settle the matter tomorrow with rapid (and perhaps blitz) tie breaks.
That means the fourth elimination came in a match where the first game was drawn. Specifically Maxime Vachier-Lagrave, playing the black side today, defeated Wesley So to earn a place among the final eight players. This was the only decisive game among players who drew yesterday, with the other three pairings on their way to tie breaks.
So four players were eliminated and four move on to the next round, while eight must play rapid games tomorrow. How did today’s results impact the picture if we look further ahead? Here is everyone’s new odds of reaching the finals, along with how many percentage points those odds increased or decreased:
|Player||Rating||New Odds of Reaching Finals||Finals Change|
|Maxime Vachier-Lagrave (FRA)||2768.0||26.2%||17.2%|
|Wei Yi (CHN)||2737.2||7.1%||6.2%|
|Peter Svidler (RUS)||2733.4||14.1%||5.8%|
|Shakhriyar Mamedyarov (AZE)||2744.2||16.1%||4.3%|
|Hikaru Nakamura (USA)||2813.6||51.4%||3.8%|
|Anish Giri (NED)||2792.1||23.8%||3.3%|
|Dmitry Andreikin (RUS)||2729.0||5.2%||1.1%|
|Dmitry Jakovenko (RUS)||2742.2||6.4%||0.8%|
|Radoslaw Wojtaszek (POL)||2741.9||6.6%||0.5%|
|Pavel Eljanov (UKR)||2743.8||6.8%||-0.3%|
|Sergey Karjakin (RUS)||2765.4||14.0%||-0.6%|
|Michael Adams (ENG)||2736.6||0.0%||-1.0%|
|Fabiano Caruana (USA)||2791.7||0.0%||-8.0%|
|Ding Liren (CHN)||2780.6||22.1%||-9.3%|
|Veselin Topalov (BUL)||2802.5||0.0%||-10.9%|
|Wesley So (USA)||2761.7||0.0%||-12.8%|
Four of the five biggest drops were of course from those players who were eliminated, but it’s perhaps interesting that Ding Liren, despite still being a favorite to advance tomorrow, took a bigger hit than two players who are now completely done. It makes some sense, perhaps. After his win yesterday, Ding was a huge favorite to move past Wei Yi, and now suddenly there is some immediate risk. Letting Wei off the hook with today’s loss does put a major dent in his goals, as he lost almost a third of his significant equity in reaching the finals. Yesterday he was the favorite to reach the finals from his half of the bracket, and today that favorite is instead Vachier-Lagrave (today’s biggest gainer by far).
It would be fair to argue that going from an 8% chance of reaching the finals down to a 0% chance (Caruana) is “worse” than dropping from 31.4% to 22.1% but still being in pretty good shape in the tournament. On the other hand, in terms of absolute percentage points Ding’s drop is better, and that’s how we choose to sort the table above. Part of this is that the table is looking only at the one-day change. If we go back to the beginning of the round, then we see that in the last two days Caruana’s odds dropped 26.1 percentage points, while Ding’s chances have actually improved by 5.7 percentage points. It’s just that most of Caruana’s fall came yesterday, and Ding’s net gain is due to a large leap yesterday, which today’s loss largely negated.
The four matches that went to tie breaks, and our estimation of the odds at this point, and how those odds changed with today’s result, are as follows (including what opponent awaits the victor in the quarterfinals):
|Favorite||Rating||Quarterfinal Odds||Change Today||Underdog||Rating||Quarterfinal Opponent||Rating|
|4. Anish Giri (NED)||2792.1||64.7%||3.4%||20. Radoslaw Wojtaszek (POL)||2741.9||21. Maxime Vachier-Lagrave (FRA)||2768.0|
|8. Ding Liren (CHN)||2780.6||63.1%||-31.1%||24. Wei Yi (CHN)||2737.2||16. Peter Svidler (RUS)||2733.4|
|11. Sergey Karjakin (RUS)||2765.4||60.9%||-5.8%||27. Dmitry Andreikin (RUS)||2729.0||19. Shakhriyar Mamedyarov (AZE)||2744.2|
|26. Pavel Eljanov (UKR)||2743.8||50.6%||-5.1%||10. Dmitry Jakovenko (RUS)||2742.2||2. Hikaru Nakamura (USA)||2813.6|