FIDE’s anti-cheating commission has recently stepped up its efforts to combat the problem. The group met last month and resolved to give financial support to national federations that need it to help them root out cheating, and will share detection techniques with online chess platforms. They are currently investigating 20 cases.

“The cheaters have been winning for a long time,” Arkady Dvorkovich, the president of FIDE, said in a telephone interview from Moscow. “But in the last few months we showed our determination to fight it and I think people realize it is serious.’”

In 2013, Borislav Ivanov, a young player from Bulgaria, was essentially forced into retirement after he refused to take off his shoes to be searched for an electronic device that might be used to transmit signals to him. A device was never found — Ivanov reportedly refused to remove his shoes because, he claimed, his socks were too smelly — but he retired shortly after the tournament.

Dominguez said he did not think the top 20 players in the world cheat: It would be too risky to their reputations, he said. But he was at the 2012 chess Olympiad in Khanty-Mansiysk, Russia, when accusations flew that the French team had used an elaborate cheating scheme. The French team was accused of sending text messages to teammates, who would then stand in prearranged spots in the gallery. Their location was supposedly the signal to a young, unproven player, Sébastien Feller, for the next move.

Feller denied the accusations but was suspended by the French chess federation, which said it discovered numerous suspicious texts. That penalty was later overruled by a French court.

Dominguez was not playing Feller, but saw the furor at the time and its effects even on clean players.

“One of the dangers is that you get a bit paranoid about these things,” Dominguez said. “Maybe in baseball as well. You feel insecure and lose focus on your game.”