The cheating scandal gripping chess has taken another turn, with five-time world champion Magnus Carlsen resigning from an online match against American teenager Hans Niemann after making just one move.
It was the pair's first meeting since Carlsen lost to the 19-year-old at the $500,000 Sinquefield Cup earlier this month and mysteriously pulled out of the tournament.
Carlsen's withdrawal from that event – which was announced via a cryptic tweet – prompted widespread speculation that the Norwegian grandmaster suspected foul play.
While Carlsen is yet to directly accuse Niemann of cheating, his early resignation from their game at the Julius Baer Generation Cup will stoke further controversy.
"Definitely a protest move," said former women's world champion Susan Polgar.
"This beef will not die down any time soon!"
Niemann has admitted to cheating in online games as a child, but has strongly defended himself against insinuations that he may have done so in recent professional games – declaring he was willing to play "naked" to prove he had no outside assistance.
He's accused Carlsen and online platform Chess.com – which has barred him from playing – of slandering his reputation.
"I believe this is completely unfair — this is a targeted attack," said Niemann earlier this month.
"They know I am not a cheater."
Carlsen's passive-aggressive handling of the situation has divided commentators.
"This is shocking and disturbing," said Jamaican-American grandmaster Maurice Ashley, after Carlsen's resignation against Niemann on Tuesday morning Australian time.
"No one can be happy that this is happening in the chess world."