Tennis brat Nick Kyrgios explodes at fan, umpire during Miami Open exit

Nick Kyrgios faces sanctioning after making an explosive exit from the ATP Masters 1000 event in Miami, then claiming he was a "little bored", so he started mimicking Roger Federer.

In a typically lively and controversial performance, Kyrgios destroyed two racquets, gave one to a fellow Boston Celtics fan and clashed with the umpire, after being docked a point for telling a spectator "f*** you man".

The combustible Canberran also produced the shot of the tournament, only to crash out 4-6 6-3 6-2 in the fourth round to 11th-seeded Croat Borna Coric.

Both players received code violations for racquet abuse, but as ever, Kyrgios provided all the talking points.

He approached chair umpire Gianluca Moscarella to sarcastically congratulate the Italian's controlling of the match, after receiving his point penalty, while down game point and serving at 2-4 in the deciding set.

Having already been warned for his behaviour, Kyrgios was left fuming.

With the match all-but lost, he shook left hands with the official at the ensuing changeover, before he continued to berate him during the sit-down.

"Really good job, well done," he said. "You've controlled the environment really, really well."

Kyrgios's earlier complaints to the umpire about crowd disturbances had fallen on deaf ears.

"You've done nothing to keep the fans from yelling out," he said.

Moscarella said the fans were merely "enjoying themselves", but Kyrgios was unrepentant after the match, taking aim for a second time at his courtside hecklers.

"They paid money to see me play and they just screamed out ridiculous things, and I'm just not going to take it anymore," Kyrgios said.

"I played for 2h 20m and the guy yells at me: 'Play some tennis!'

"I'm not going to take it, so I just said 'F you' to him.

"Probably not needed, but at that time, I'd been competing and in the heat of the moment, and it's not what you want to hear."

The crowd certainly would have enjoyed Kyrgios's extraordinary shot-making.

After calling the trainer to have his knee strapped after just three games, the temperamental talent pulled off an audacious on-the-run winner past the advancing Croatian on the way to taking the opening set from 3-1 down.

"Get outa here, Nick Kyrgios - that's insanely good," a commentator gushed, before the Australian once again mentally unravelled.

The giant-killing run of Kyrgios's countryman, Jordan Thompson, came to an end with a 7-5 7-5 fourth-round loss to South African sixth seed Kevin Anderson.

Canadian teenager Felix Auger-Aliassime became the first qualifier to reach the quarter-finals in 12 years, after taking out 17th seed Nikoloz Basilashvili 7-6 (7-4) 6-4.

Defending champion John Isner also advanced with a 7-6 (7-5) 7-6 (7-3) win over Brit Kyle Edmund.

AAP