Hans Niemann's credibility has been tested by an investigation into his play that says he "likely received illegal assistance in more than 100 online games”. A report from Chess.com, first detailed Tuesday by the Wall Street Journal, says such cheating occurred as recently as 2020, and many instances involved matches in which Niemann was playing for prize money.

The Chess.com investigation used the platform's own array of computerized and manual cheating-detection tools to analyze Niemann's play over years of matches. Niemann himself has described Chess.com as having "the best cheat detection in the world."

World champion says Niemann cheats

Just last week, the top-ranked chess player in the world, reigning five-time world champion Magnus Carlsen of Norway, forthrightly accused Niemann of cheating in over-the-board or face-to-face matches, including when Niemann dealt Carlsen his first loss in 54 matches on September 4.

Chess.com's report says Carlsen's accusation played no role in its investigation, adding that its findings point to incidences in online matches. "While Hans (Niemann) has had a record-setting and remarkable rise in rating and strength,” the report says, "in our view there is a lack of concrete statistical evidence that he cheated in his game with Magnus or in any other over-the-board ("OTB")—i.e., in-person games."

Still, the report pointed to "many remarkable signals and unusual patterns in Hans' path as a player, saying some games, behaviors, and actions are hard to understand."

It should be noted that Chess.com is moving toward the purchase of Magnus Carlsen's own app called Play Magnus. Chess.com's more than 90 million members include some grandmasters, and the platform hosts major tournaments for prize money.

While other chess grandmasters have expressed doubts about Niemann's rise to the top 50 in the game, or suggested he has cheated, a number of experts and historians have been quoted saying they have not seen rock solid evidence of impropriety on Niemann's part.

Niemann admits cheating when young

Niemann has admitted to cheating with the use of an electronic device to determine the best moves, once at the age of 12 and again at the age of 16. He apologized, blaming his youth at the time and saying he hasn't cheated since.

His admissions came after Carlsen pointedly took his stand on Niemann's alleged cheating. Carlsen dramatically resigned after one move in an online match against Niemann on September 19, then released a statement saying he would not "play against people that have cheated repeatedly in the past".

He added,"I believe that Hans Niemann has cheated more — and more recently — than he has publicly admitted. His over the board progress has been unusual, and throughout our game in the Sinquefield Cup [the September 4 match in which Carlsen lost] I had the impression that he wasn't tense or even fully concentrating on the game in critical positions, while outplaying me as black [pieces, a disadvantage in chess] in a way I think only a handful of players can do."

Chess.com said in its report, "we believe certain aspects of the September 4 game were suspicious."

Chess moves data

One paragraph of the report goes into some detail about Hans Niemann's play in the tournament in question, the Sinquefield Cup. It noted that his win over Carlsen in the third round was apparently seen as suspicious, perhaps relying on assistance from an outside source watching the live video feed.

"We also measured that for the first three games of the Sinquefield Cup, Hans played with a Chess.com Strength Score of 97.17. After round 3, the event organizers (in response to cheating concerns) added a 15-minute delay to the broadcast of the chess moves. For rounds 4-9, Hans achieved a Strength Score of 86.31. Other players also had some interesting changes in Strength, as measured by Chess.com. This can be attributed to any number of factors, including the ensuing situation after Magnus withdrew, different opponents, etc. In our view, no conclusions should be made from this data."

Prior to their game on September 4, both Niemann and Carlsen were given security checks with metal detector wands, as seen in video from the tournament.

The Chess.com report added that while the investigation results focus on Niemann's online matches, six of his best over-the-board, in-person matches "merit further investigation based on the data."