A showboating eSports star dubbed "the Korean Conor McGregor" played part of a one-sided final using his bare toes, provoking a furious response from his humiliated Chinese rival.
South Korea's Lim Hong-Gyu at another point folded his arms and pretended to sleep as he thrashed Luo "Legend" Xian in their StarCraft: Remastered showdown in the United States.
The bout -- which pitted the two players against each other in a hugely popular sci-fi strategy game -- was watched by thousands of fans online and sparked debate about whether Lim was arrogant or brilliant.
Luo consequently branded Lim -- better known by his playing nickname "Larva" and likened to the brash and colourful Irish MMA star McGregor -- "a clown".
US organisers were also unamused by Lim's antics during the Zotac Cup Masters event on Sunday.
"It is unfortunate that the behaviour of one of the players may have caused an uproar in the professional gaming community, however, it does not speak for nor does it represent Zotac or the Zotac Cups," a statement read.
It added: "Hereby we sincerely apologise to our fans, the Zotac Cup community and any players or persons impacted by the incident."
A separate statement in Chinese on Weibo, China's version of Twitter, said Lim would not be allowed to take part again.
But that did not placate Luo or Chinese eSports fans.
An angry Luo hit out at his Korean opponent on Weibo, writing: "What kind of fun could you have got from this or is this to win some idiot fans?
"When I first heard about you, I thought you got the success you deserved for your efforts. I thought that was inspiring.
"Now I see that I was blind. Your behaviour is just that of a clown," Luo added.
"This is the difference between you and a champion player. Trash."
Lim's behaviour stirred fierce debate among eSports enthusiasts, with some saying he was unprofessional but others applauding his audaciousness after using his left foot to play, while keeping his right hand on the computer mouse.
Experts commentating on the game as it unfolded were impressed however.
"He's just a beautiful human being," said one broadcaster.
"This is literally a joke that players would use in StarCraft to say, 'I can beat you playing with my feet.'"
Speaking via a translator in a post match interview, Lim said he often played with his feet outside of tournaments.
"You should only do it against people that you are 100 percent confident of beating with your feet," he added.