The world's top-rated player will have to win in the next game for a chance to stay in the World Cup. All the other top favourites ended the day with a draw

In a surprising turn of events, the world's highest-rated player Magnus Carlsen suffered his first defeat in the World Cup and the first ever to 18-year-old German prodigy Vincent Keymer. Carlsen misplayed an even endgame and ended up lost. All other top favourites in the Open – Nakamura, Caruana and Nepomniachtchi, finished the day with a draw.

Of the eight games played in the Women's tournament, all ended in a draw save one: India's top-rated woman player and world #4, Humpy Koneru, lost as White to Georgia's Bella Khotenashvili.

The Open Tournament Highlights

Former World Champion in classical chess, Magnus Carlsen, suffered a defeat as Black against 18-year-old German prodigy Vincent Keymer. This was the first time that Keymer beat Carlsen in a classical game.

Playing as Black in the Queen's Gambit Declined, Carlsen created a solid position in a typical Carlsbad structure. In a rook and knight endgame that transpired, Carlsen made a mistake on move 36 and ended up losing a pawn. Soon afterwards, the rooks were exchanged and in a knights endgame where Vincent smoothly converted his extra pawn.

Keymer was realistic when asked to sum up the game: "It was an equal game, and then I got a chance and used it… This was a one-off blunder [for Carlsen] otherwise, the game would have ended with a draw which would have been totally fine with me."

To stay in the race, Carlsen will have to win the second game, where he will be playing as White.

In another upset, Alexey Sarana beat Wesley So with black pieces. In the exchange line of the Queen's Gambit Declined, the reigning European champion gradually outplayed his opponent. By move 23, Sarana was significantly better.

Wesley So then managed to get close to equal after a mistake by Sarana, but in the proceeding moves, he made a drastic error of judgement and was lost again. Sarana finished off the opponent with several impressive moves. 

Three other grandmasters won today – Nils Grandelius beat Jamie Santos Latasa, Vidit defeated Bacrot in a sharp Sicilian battle, and Hungary's Ferenc Berkes is continuing his impressive run, outplaying Ruslan Ponomariov.

All other games ended in a draw, including those of Caruana, Nakamura, and Nepomniascthi.

The Women's Tournament Highlights

The Women's tournament saw Bella Khotenashvili secure the only victory of the day by defeating India's top-rated woman player, Humpy Koneru, with black pieces. After Koneru made a mistake early on in the opening, she ended up defending a weaker position throughout the game. Despite Khotenashvili giving Koneru a few chances to equalise, in the end, the Indian didn't use them and was forced to surrender after 42 moves.

Round four saw an unusual pairing where two sisters – Anna and Mariya Muzychuk had to play against one another. In the Semi-Tarrasch, neither side managed to get much advantage, and the two agreed to a draw after reaching an even rook endgame.

Women's World Champion Ju Wenjun drew as White with Elisabeth Paehtz in what was a largely calm game. Serbia's Teodora Injac had a nearly winning position as White against Polina Shuvalova in the opening but misplayed in the middlegame and her advantage gradually evaporated.

The full results of today's round can be found here: worldcup2023.fide.com/pairings.

Game two of round four will take place on Thursday, 10th of August at 3 PM local time in Baku, Azerbaijan.

Here follows a closer look at some of the top games of round four of the World Cup:

Germany's Vincent Keymer achieved the biggest game victory of his career as he defeated Magnus Carlsen for the first time in a classical game.

In the Queen's Gambit Declined, Carlsen had an equal position, but he blundered on move 36.

White just played g5. The best option for Black was to plat his knight to e7, to try and force an exchange of knights. Instead, Carlsen played 36…Nc7? which failed to 

37.Nd6! g6 Played to prevent White from placing the rook on f5, attacking the f7-point.

However, after 38.Nxb7 Rb1 39.Nd8 Rb5 40.Rxb5 cxb5 41.Nc6, the knight endgame is hopeless for Black. Carlsen resigned on move 58. 1-0

Wesley So – who has had a lot of luck in the World Cup so far – wasn't lucky today. Alexey Sarana (now playing for Serbia) outplayed the American in the Queen's Gambit Declined.

By this point, Black had already gained more space and initiative over the board. White should have tried to ease the pressure by exchanging a pair of rooks with 23.Rxc8 followed by Qb4. So, however, went for 23.Qd3? giving Black a precious tempi 23…Rxc1 24.Rxc1 and now Sarana chose the wrong path for his knight with 24…Ng4. 24…Nd7, with the same idea of Ne5, was a preferred move by the engines.

25.Qf5 Nf6 – Sarana admits his mistake. 26.Nc5 h5 and now, 27.b4? 

After 27.Qg5! Black is just slightly better. 

Now Black pressed on. After 27…h4 28.Nf1 g6 29.Qd3 Nh5 Sarana dominates. The final portion of the game is quite spectacular.

29…Nh5 30.Qxa6 Qxa6 31.Nxa6 Nf4 32.Nc7

This last try by Wesly was met with 32...h3! 33.Ng3 hxg2 34.Nxa8 d3, and there's no way for White to stop the Black from promoting the d-pawn. 0-1

Humpy Koneru lost as White to Bella Khotenashvili from Georgia. Things started to go south for India's top woman player as early as move seven.

In the Queen's Gambit Declined, Bella introduced an interesting novelty 6...b5. Humpy's reaction 7.a4? was far from optimal. 7.Nxb5 or 7.e5 were the best options.

After 7…b4 8.Ne2 Bb7 9.Ng3 b3 10.Qxc4 Nxe4 Black emerged clearly better but dropped most part of his advantage in subsequent play. 

Black now has only a slight edge. White should have played 22.Rd1 and proceeded with gradually consolidating her position. Instead, Humpy opted for a natural but erroneous 22.Be3?

After 22…Nxe3 23.fxe3 Qh8 24.b3 e5 25.Qf2 e4 26.Rhd1 f4 Black is dominating with opposite-colored bishops only reinforcing her attack. 

The rest was a smooth sail for Bella. 0-1, 42 moves. 

Text: Milan Dinic

Photo: Stev Bonhage, Anna Shtourman and Maria Emelianova (chess.com)

About the event

The FIDE World Cup 2023 is taking place from 29 July to 25 August 2023 in Baku, Azerbaijan.

In the Open tournament, 206 players were eligible to take part and 103 in the Women's event.

There will be eight rounds in the Open and seven in the Women's tournament. Each round will be played under a knock-out system, consisting of a 2-game match. In the case of a tie, the players will play a rapid and, if necessary, a blitz tiebreak until the winner is determined.

The winners of the top three places in both sections will qualify for the 2024 Candidates tournament.

In both events, the time control for each game is 90 minutes for the first 40 moves, followed by 30 minutes for the rest of the game with an increment of 30 seconds per move starting from move 1.

The prize fund for the entire event is 2.5 million US Dollars, with $1,834,000 in the Open and $676,250 in the Women's tournament. The 2023 FIDE World Cup has the largest prize fund for any chess tournament ever played.

More information about the event: worldcup2023.fide.com/

Regulations: 

Open tournament: handbook.fide.com/files/handbook/WorldCup2023Regulations.pdf 

Women's event: handbook.fide.com/files/handbook/WWorldCup2023Regulations.pdf

Schedule: worldcup2023.fide.com/schedule