Polish chess grandmaster Jan-Krzysztof Duda refused to shake the hand of his Russian opponent Denis Khismatullin during the International Chess Federation’s World Rapid and Blitz Chess Championships, footage from the event shows. Khistamullin has not filed a formal complaint about the snub.

The high-profile tournament took place in Uzbekistan in the last few days of December although the incident only made headlines on Tuesday after a video of it surfaced online.

In the footage, Khismatullin is captured extending his hand towards Duda, a part of the competition that is obligatory before the start of a match, and the Pole is seen refusing the gesture.

Their game ended in a draw. According to World Chess Federation (FIDE) rules, the handshake between opponents is a mark of mutual of respect ahead of every game. Duda could’ve been disqualified if Khismatullin filed a complaint, but the Russian opted not to go this route, newspaper Sport-Express newspaper reported.