Frances Tiafoe launched into a foul-mouthed tirade directed at a chair umpire after the American received a time violation and then lost to Roman Safiullin in the third round of the Shanghai Masters on Tuesday.

Unseeded Safiullin beat 13th seed Tiafoe 5-7 7-5 7-6(5) in a three-hour contest where the American initially received a time violation while serving with the score tied at 5-5 during the final set tiebreak.

“No, no, I tossed the ball up… I was ready to serve. Dude, that’s the rule,” Tiafoe said repeatedly as he walked towards the net while trying to convince the Ecuadorian chair umpire Jimmy Pinoargote.

“I’m not buying it, it’s the second serve,” the umpire said in response, putting an end to the discussion by announcing “second serve” on the microphone. Tiafoe went on to lose the point and eventually the match.

Moment which lead to Tiafoe lashing out on the umpire.

Umpire gave him time violation warning and took his first serve away.

He said ‘I’m not buying it, this is now second serve’

Tiafoe said ‘ I tossed the ball, this is the rule’

pic.twitter.com/hBDAAamvrm

— edgeAI (@edgeAIapp) October 8, 2024

After shaking Safiullin’s hand at the net, Tiafoe directed his anger at Pinoargote, repeatedly hurling expletives at the umpire as he walked back to his seat, as the small crowd of fans who had stayed behind laughed at his antics.

the drama at the end of the tiafoe/safiullin match pic.twitter.com/HftfltXHew

— emily (@sportyandhot) October 8, 2024

The ATP did not immediately comment on the incident but the rule-book says the 26-year-old can expect to be fined, with the amount going up to $60,000 for each violation at Masters 1000 tournaments.

Tiafoe later apologised for his furious outburst at the umpire.

“I really apologise for the way I acted,” the world number 17 wrote on Instagram. “That is not who I am and not how I want to treat people.”

Frances Tiafoe on Instagram.

Well done 👏 pic.twitter.com/BuJXG6sEyP

— José Morgado (@josemorgado) October 8, 2024

The world number 17, Tiafoe, had enjoyed some late-season form where he reached the finals of the Citi Open and the Cincinnati Open while he also advanced to the semi-finals of the US Open.