American tennis star Frances Tiafoe insults the referee in a fiery tirade after losing the Shanghai Masters

American tennis star Frances Tiafoe apologized on Tuesday after shocking fans when he insulted a referee following his third-round loss at the Shanghai Masters on Tuesday.

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

Frances Tiafoe of the United States returns a shot during the men's second-round singles match at the Shanghai Masters tennis tournament at the Qizhong Forest Sports City Tennis Center in Shanghai, China, Monday, October 7, 2024. (AP Photo/Andy Wong)

Immediately after shaking hands, Tiafoe walked up to the officer.

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

According to the Associated Press, Tiafoe yelled about 10 profanities toward officer Jimmy Pinoargote during a minute-long tirade.

He later posted an apology on his social media.

“I truly apologize for the way I behaved tonight. This is not who I am and not the way I would ever want to treat people,” he said in a message shared on his Instagram Stories.

Frances Tiafoe from the USA celebrates his victory in the round of 64 against China's Zhou Yi. (REUTERS/Tingshu Wang)

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“I let my frustration out in the heat of the moment and am extremely disappointed with how I handled the situation. This is not acceptable behavior and I would like to apologize to the referee, the tournament and the fans.” will be better for all of you.

The outburst was apparently a reaction to a time violation he sustained when the score was 5-5 in the decisive tiebreaker. He was denied his first serve after Pinoargote realized he wasn't making a real attempt to serve.

He lost that point and the next one, losing the match.

Frances Tiafoe of the United States celebrates winning against Carlos Alcaraz of Spain during their men's singles semifinal match on day twelf of the 2022 US Open at the USTA Billie Jean King National Tennis Center on September 9, 2022 in the Flushing borough 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 ATP Tour rules, he could be fined $60,000 for this verbal abuse of an official, You will forfeit the prize money, otherwise the matter could be subject to further investigation.

The Associated Press contributed to this report.

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