In the feud with world chess champion Magnus Carlsen, the young US player Hans Niemann launched a big counterattack: The 19-year-old American has now filed a lawsuit against the Norwegian Carlsen in a court in the US state of Missouri: Niemann is demanding no less than 100 million dollars (102 million euros) in damages from Carlsen as well as from Carlsen’s company Play Magnus and the two US chess players Danny Rensch and Hikaru Nakamura. Niemann accuses them of defamation and slander as well as secret collusion in order to destroy his reputation and his existence.

The controversy surrounding Carlsen and Niemann has been causing a stir in the chess world for weeks. Carlsen had withdrawn from a chess tournament in the United States in early September after Niemann beat him there. Two weeks later, Carlsen abandoned a game against Niemann at an online chess tournament after just one move. At the end of September, the 31-year-old made specific allegations of fraud against 19-year-old Niemann for the first time. Carlsen explained that Niemann cheated more often than he admitted – even recently.

Niemann had previously admitted to cheating twice in online chess tournaments – once at the age of 12 and once at the age of 16. However, Niemann assured that he had never cheated in a face-to-face tournament. He even offered to play naked so trickery could be ruled out.

In early September, chess website chess.com banned Niemann from further using the platform because he had “probably cheated in more than 100 online chess games” at chess.com.

In his lawsuit, Niemann accuses Norwegian Carlsen and US players Rensch and Nakamura of causing “devastating damage” to his reputation and career. After Niemann’s win at the Sinquefield Cup in Missouri, Carlsen “viciously retaliated by falsely accusing Niemann of somehow cheating during their face-to-face game without evidence,” the lawsuit states.

Chess.com has banned Niemann from its website and all future events “to lend credibility to Carlsen’s baseless and defamatory allegations of cheating.” Chess streamer Nakamura “reinforced” Carlsen’s “false allegations of cheating” in hours of live video.

Niemann also suggests in his lawsuit that his ban from chess.com came under pressure from Carlsen, whose company Play Magnus is being acquired by chess.com for $83 million. As the “King of Chess”, Carlsen assumes “that he can do whatever he wants in chess and that he will get away with it,” criticized Niemann.