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If you were getting used to just one decisive game per round, then Sunday’s round rocks your world with three decisive games, lots of blunders, and electrifying action.
Winners were GM Wesley So who prevailed over co-loader GM Ian Nepomniachtchi in an endgame, GM Maxime Vachier-Lagrave who took down GM Fabiano Caruana when the latter took one chance too many, and finally, GM Levon Aronian who defeated fellow American GM Leinier Dominguez.
After four rounds, So is in sole possession of the lead, trailed by GM Bogdan-Daniel Deac, Vachier-Lagrave, and Aronian, all half a point behind.
Round five will begin on Monday, May 9, at 5 a.m. PT / 14:00 Central Europe.
In the game between two of the leaders, So and Nepomniachtchi, the players explored a line that the latter had prepared for his world championship match against World Champion Magnus Carlsen last year in Dubai. The line in question is the Catalan Opening, Accepted Variation where Black answers White’s 7.Qc2 with 7…b5. This variation is a gambit that the world champion did not feel inclined to accept, but So did.
Part of the narrative is that both Nepomniachtchi and So have previous experience in this line, So as White, beating GM Hikaru Nakamura in an online game, and Nepomniachtchi in multiple games, including one against GM Anish Giri from the World Rapid/Blitz Championship in Warsaw last year.
In fact, the players followed that game against Giri through move 21, after which So varied with 22.e3. Giri opted for an endgame with a knight and four pawns vs. a bishop and three pawns and with a queen and rook for each as well. He was unable to present Black with any serious trouble. So, therefore, tried where they had opposite-colored bishops, hoping that this would offer him better winning chances. It is a well-known theme that opposite-colored bishops offer the side with the initiative the upper hand.
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However, it honestly did not look like So would have any success and that Nepomniachtchi would have luck with his defensive strategy. But then things started going awry for him. The first puzzling decision was the pawn advance 44…g6. There is nothing immediately wrong with the move, and possibly Nepomniachtchi wanted to prevent So from aligning his pieces with the bishop on d3 and the queen on e4 to penetrate on h7, but this plan was quite easy to prevent with a queen to e5.
After splitting the pawns, White’s advantage was still minimal, but then came the next mistake, 53…Qf5, that allowed White to push his e-pawn forward to e4 and, shortly after another mistake, allowed it to come to e5. Then after a final blunder, 57…Qg6??, White could crown his efforts with a combination, winning a second pawn, which caused Black to resign on the spot.
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Co-commentator GM Jon-Ludwig Hammer seriously questioned Nepomniachtchi’s strategy in this game and was truly baffled by the fact that this opening line was indeed intended to be played against Carlsen who has made a living of chewing people up in endgames such as this one.
Last year’s winner GM Shakhriyar Mamedyarov as White had to face co-leader and local hero Deac. Against Mamedyarov’s Queen’s Gambit, Deac defended with the currently highly popular Vienna/Ragozin Defense, which is something he has used several times over the past couple of years, including in the recent European Individual Championship.
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Mamedyarov brought his own canister of gasoline and started pouring it on the board right out the opening, signaling his intentions to blow Black off the board in a kingside attack.
However, Deac, clearly boosted by Saturday’s surprise win confidently defended, took the sacrificed pawns, and seemed to hold an advantage. A few small inaccuracies from Deac allowed White an opportunity to win back the sacrificed material and enter an equal endgame where the players found a way to repeat moves up to the time control at move 40.
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Two players who must be unhappy with their results so far are GMs Alireza Firouzja and Richard Rapport. In round three, Firouzja seemed bound to win against Aronian but had to settle for a draw, while Rapport was clearly winning against Deac but blundered multiple times on the way to ultimately losing the game.
In a sharp Sicilian, Firouzja played a line that sent his king wandering up to f3, much like Aronian’s king in round three. This, however, is familiar territory and well-known theory; the line has been played in nearly 400 games in my database.
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On move 17, White took the game into less well-known territory with his 17.Be2 that seems to offer White an edge. Rapport, however, responded accurately and found his way into an endgame that looked unpleasant but seemed fully playable after active but precise defense by Black.
An interesting highlight of the game is when Rapport switched from defending passively to actively pursuing a perpetual check with his two rooks, letting White’s a-pawn run, but then suddenly thinking for more than 15 minutes before continuing.
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In the end, Rapport settled down and found the right way forward, and the players started repeating moves.
Last week, Dominguez and Aronian played a mini-match to determine who would face Caruana in the final of The American Cup, and now they had to face each other again. Like in St. Louis, Dominguez invited his opponent to an Italian Game, and this time he got it. Aronian was first to depart from known theory with his 10…a5!? that seemed curious but playable. White, nevertheless, got a small advantage.
However, several inaccuracies, as well as an outright mistake, gave Black an advantage, allowing Aronian to win a pawn. At this juncture, it looked like an easy technical win for Black. Then, however, Aronian started playing sloppily and let Dominguez back into the game.
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After having fought against the wall in severe time trouble, Dominguez had almost equalized. Then almost immediately after the time control, on move 44, he blundered, allowing Aronian to force White into a lost endgame, which was converted with a safe hand.
Vachier-Lagrave had thus far had an unremarkable tournament, not getting any positions where he could play for a win with either color.
Caruana clearly came to fight, playing the Open Variation against the Frenchman’s Ruy Lopez and then entering the Dilworth Attack, 11…Nxf2!? where Black gives up two minor pieces for a rook and a pawn. However, rather than entering the main line, Vachier-Lagrave went for a rare line he has used on a couple of occasions before, where he gives up another pawn to get his pieces into play better.
Black departed from those earlier Vachier-Lagrave games by playing 15…Qd7, which is not exactly loved by the engine. However, after several inaccurate moves by White, Black took the initiative and on move 20 could have played 20…b4 followed by 21…Nd4 with something close to a clear advantage.
However, instead, Caruana played the wild 20…Rxf3?, which gave White a clear advantage. It is not entirely clear what Caruana had missed in his calculations, but his attack was fairly easily warded off by Vachier-Lagrave.
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After White’s 27.Bg3!, it was clear that Black did not have enough attack to compensate for his sacrificed material. Although he continued for a bit, the result was never in doubt.
Round 4 Standings
All Games Round 4
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