Plenty has been said about Nick Kyrgios' temper at Wimbledon this week, but the young Australian was defiant over his use of foul language during a second-round win on Wednesday.
Kyrgios saw off Juan Monaco 7-6(5), 6-3, 6-4 and now meets Milos Raonic, the man who brought him crashing back down to earth after his shock win over Rafael Nadal in the last 16 a year ago.
However, as with his first-round victory, the 20-year-old's win attracted controversy. He was reported to the umpire by a linesman for uttering a string of expletives, having hit an errant shot at 6-5 in the opening set.
That prompted Kyrgios to confront the umpire, demanding to know what the linesman had said, before losing his temper. "Does it feel good to be up there in that chair? Does it feel strong to be up in the chair?" he said.
He later revealed in his post-match press conference that a sinus infection, which he said has been giving him "blurry vision", contributed to him losing his cool in record temperatures.
"I don't know what he said. I was just asking the umpire what the line judge said. I was just curious. I wasn't causing any drama there," said Kyrgios.
"I'm aware of what I'm saying. I'm in pain and I'm playing a tennis match at Wimbledon second round. A bit of stress out there. I guess that's why he did it.
"I just thought he thought he was top dog in the chair really. He was telling me not to speak to him, all that stuff. Doesn't really matter, you know."
Kyrgios is no stranger to controversy at the All England Club. He risked a fine for an on-court outburst during his first-round win over Diego Schwartzman, insisting he was calling himself "dirty scum" rather than the umpire after contesting a call in the third set.
Against Monaco, he also appeared to lose his temper with the Aussie Fanatics fan group, who sung loudly from the front row of Court 18 throughout the match.
The fans began singing to drown out the sound while Kyrgios disagreed with the umpire, prompting the player to tell them "now is not a good time" and to "stop it".
"I can't even remember saying that," Kyrgios added in his press conference, however.