Weissenhaus Freestyle Chess Grand Slam

Qualification

All qualification matches were played online and hosted by Chess.com. Non-titled players began in one of two open qualifier events on January 4 and January 5, with 196 participants; the top three from each advanced to the Swiss stage. The Swiss stage on January 6 was open to all titled players and had 248 participants; the top four—Vladimir Fedoseev, Denis Lazavik, Javokhir Sindarov, and Olexandr Bortnyk—moved to the 16-player knockout stage. Twelve players from the Freestyle Chess Players Club were invited directly to the knockout stage, held on January 7 and 8, seeded by their December 2024 classical FIDE rankings. Fedoseev defeated Sindarov in the final via an armageddon game after a 2–2 tie, qualifying for the Grand Slam; after Viswanathan Anand withdrew, Sindarov also qualified.

Main event

The main event began with a rapid round-robin stage using a time control of 10 minutes plus 10 seconds per move. Players finishing 1st through 8th advanced to the classical knockout stage. On the first day, Javokhir Sindarov went undefeated with four wins in five games, including a victory over Magnus Carlsen, and ended the day tied with Fabiano Caruana after their fifth-round draw. On the second day, Alireza Firouzja defeated Sindarov in the final round, securing first place in the round-robin on tiebreaks and the right to select his quarterfinal opponent first.

Levon Aronian and Vladimir Fedoseev were eliminated from the main competition and played a match for ninth place. The knockout stage matches consisted of two games at 90 minutes plus 30 seconds per move; tiebreaks were two 10+10 rapid games, then two 5+2 blitz games if needed, then one armageddon game with bidding. Players finishing 1st–4th in the round-robin chose their opponents from those finishing 5th–8th and decided whether to play white or black in the first game. The four quarterfinal losers competed in the 5th-to-8th-place bracket.