American tennis star Frances Tiafoe issued an apology on Tuesday after he shocked fans when he blasted profanities at a chair umpire following his third round loss at the Shanghai Masters on Tuesday.

The U.S. Open semifinalist was upset by 61st-ranked Roman Safiullin in a 5-7, 7-5, 7-6 (5) loss.

Immediately after shaking hands, Tiafoe moved on to the official. 

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“F— you, man,” a visibly frustrated Tiafoe shouted. “F— you. Seriously man, f— you.” 

According to The Associated Press, Tiafoe shouted about 10 expletives in the direction of official Jimmy Pinoargote during a minute-long tirade. 

He later posted an apology to his social media.

“I really apologize for the way I acted tonight. That is not who I am and not how I ever want to treat people,” he said in a message shared to his Instagram Stories.

Frances Tiafoe of the U.S. celebrates after winning his round of 64 match against China’s Zhou Yi.  (REUTERS/Tingshu Wang)

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“I let my frustration in the heat of the moment get the best of me and I’m extremely disappointed with how I handled the situation. That’s not acceptable behavior and I want to apologize to the umpire, the tournament, and the fans. I’ll be better for y’all.” 

The outburst was seemingly in reaction to a time violation he received at 5-5 in the decisive tiebreaker. He was docked his first serve after Pinoargote found he was not making a genuine attempt to serve.

He lost that point and the next to lose the match. 

Frances Tiafoe of the United States celebrates winning a game against Carlos Alcaraz of Spain during their Men’s Singles Semifinal match on Day Twelve of the 2022 US Open at USTA Billie Jean King National Tennis Center on September 09, 2022 in the Flushing neighborhood of the Queens borough of New York City. (Julian Finney/Getty Images)

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Tiafoe could face harsh punishment for the outburst. 

According to the ATP Tour rulebook, he could be fined $60,000 for the verbal abuse of an official, lose out on prize money, or the matter could be subjected to further investigation. 

The Associated Press contributed to this report. 

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