Jared Donaldson squared up to French umpire Arnaud Gabas after losing his cool over a line call in bizarre scenes at the Monte Carlo Masters on Monday.
After Gabas got out of his chair to check a mark, Donaldson lost his composure when a serve from opponent Albert Ramos-Vinolas was called in when he thought it was out.
The 21-year-old Donaldson was adamant Gabas checked the wrong mark and squared up to the official while shouting at him insisting that what the umpire was pointing at "wasn't a mark".
He then refused to play the next game until a supervisor was called to the court, claiming "I can call the supervisor whenever I want".
Donaldson later offered Gabas a sarcastic apology, saying: "I'm sorry I hurt your feelings, I apologise."
Hawk-Eye replays appeared to show that Donaldson was right about the serve when shown on television replays, but the system is not used at the tournament.
Last year's Monte Carlo runner-up Ramos-Vinolas led by a set and a break at the time, and went on to win 6-3 6-3.
Coverage of the ATP Monte Carlo Rolex Masters gets underway from 10am on Sky Sports Arena every day this week.
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