Denis Shapovalov was livid when he was not allowed to take a bathroom break midway through his Australian Open first-round win over Jannik Sinner.
Canada's 11th seed eventually saw off the up-and-coming Italian in five sets, 3-6, 6-3, 6-2, 4-6, 6-4 in a match which finished around 1am, local time.
The umpire wouldn't allow Shapovalov to head off court after the fourth set - which he had dropped to his opponent.
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"What happens if I go?", he asked, "Do I get a fine? I don't care!
"What do you mean I can't go? Are you going to disqualify me? I have to pee!"
'I'm going to p*** my pants!' - Shapovalov blows top over bathroom break
It became evident that he was not going to be permitted to relieve himself off court - and the 21-year-old stepped up his tirade at an umpire who seemed to be amused by the entire saga.
"I'm going to p*** my pants!" he declared.
"I'm going to p*** in a bottle!
"You guys are not allowing players to p***? I don't understand this rule!"
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On commentary, Eurosport's Simon Reed offered a sympathetic voice.
"It's a crazy rule," he said. "He's got a point. It's absolutely ridiculous. Why on earth can he not go to the toilet right now? It is unfathomable."
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Speaking after the match, Shapovalov cut a calmer figure and didn't blame the umpire, but called for the regulations to change: "I was just blowing off steam, just kind of cooling my head, getting rid of it.
"But also, I do think it's a dumb rule. Especially for me, I've got the smallest bladder ever, so I literally got to take a p*** every set. So it's difficult, especially when you're on that court for so long.
"Before the match I'm trying to hydrate as much as possible, so yeah, I gotta pee, man."
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