Nick Kyrgios has blown up at a Miami Open chair umpire following a number of 'questionable' line calls during a doubles defeat.
The Australian reached the third round of the singles tournament with a a disciplined win on Saturday morning (AEDT).
But on Sunday, he and American Taylor Fritz were beaten in the doubles by Guido Pella and Joao Sousa, who won 7-6 (7-4) 6-7 (3-7) 10-8 - and what followed was anything but disciplined.
In a video captured by tennis fan Ken, it showed a confrontation with the Aussie and the chair umpire.
"What the f**k is wrong with you?" Kyrgios screamed at the umpire. "You're a f**king disgrace. F**king disgrace."
The 23-year-old is then seen smashing his racquet in front of the chair.
The blow-up began during the match, with Kyrgios and Fritz docked a point after a second code violation for verbal abuse.
It's not the first time this week Kyrgios has been angered by umpires at the Miami Open, which has seen courts and officials stretched thin by rain delays and subsequent expanded schedules.
In his singles win over Alexander Bublik, Kyrgios questioned why a line judge was able to make multiple mistakes without receiving fines - unlike players.
"You think that's alright? You think it's alright: yes or no?" he asked a person sitting behind the umpire.
"Yes or no? That's not an answer. He's a disgrace. [I] come out here and play 100 percent, and deal with idiots like him."
Repeating an argument from his win over Bublik, Kyrgios added: "Does he get fined for his mistakes? It's rubbish, man."
The fan who recorded the video said line calls and overrules by the chair umpire were to blame.