Frances Tiafoe lashed out with a series of F bombs towards chair umpire Jimmy Pinoargote after losing to Roman Safiullin in the third round of the Rolex Shanghai Masters Tuesday.

Safiullin prevailed, 5-7, 7-5, 7-6 (5), in three hours and four minutes.

The American’s expletive-filled eruption was the result of a penalty he incurred at 5-5 in the final-set tiebreaker. With the serve clock approaching zero, Tiafoe tossed the ball up before letting it hit the ground.

Pinoargote then issued a time violation, loss of first serve.

“I tossed the ball. I was ready to serve,” pleaded Tiafoe when approaching the Ecuardorian.

Responded Pinoargote, “I’m not buying this, it’s the second serve now.”

Continued the No. 13 seed, “Dude, that’s the rule. The ball goes up, how am I not ready to serve?”

The two-time US Open semifinalist would ultimately lose the point at the net after being outfoxed by Safiullin. The Russian then stepped to the line and closed out the hard-fought encounter, leading to Tiafoe’s choice words for Pinoargote.

“F— you, man! F— you. Seriously, f— you. You f—ed me in this f—ing match.”

Safiullin advanced to face four-time champion Novak Djokovic, a 6-1, 6-2 winner over Flavio Cobolli.

Tiafoe later took to Instagram to express regret for his actions.

“I really apologize for the way I acted tonight. That Is not who I am and not how I ever want to treat people,” Tiafoe said.

“I let my frustration in the heat of the moment get the best of me and I’m extremely disappointed with how I handed 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.”

Word on whether Tiafoe will be fined for his actions is yet to be announced.