Nick Kyrgios had a lengthy argument with umpire Damien Dumusois during his first-round defeat to qualifier Bradley Klahn at the Shanghai Masters on Monday.
The second set of the match, which American world number 104 Klahn won 4-6, 6-4, 6-3, saw Frenchman Dumusois at one stage tell Kyrgios: “Nick – last point was really borderline.”
The Australian, who is ranked 38th in the world, responded by saying he did not care, before adding: “You have no right to tell me it’s poor.”
It was the first of a number of exchanges between the pair about Dumusois’ initial comment.
At another moment Kyrgios served an ace past Klahn and asked Dumusois: “Was that borderline poor?”
He later said to the umpire: “You know I literally could just go to the ATP office after this and say I just felt put down from your comment and you’d be in trouble, right?
“I could literally just say I couldn’t play after that because I just felt put down. You realise that, right? I’m not going to do it, but I’m just saying.”
Last month, umpire Mohamed Lahyani was suspended from his next two scheduled tournaments after trying to encourage Kyrgios during a match at the US Open.
Lahyani took the unusual step of climbing down from his chair and having a lengthy chat with Kyrgios when he was showing little effort as he trailed by a set and 3-0 down against against Pierre-Hugues Herbert.
Stan Wawrinka was also among the players to make a round-one exit in Shanghai.
The Swiss three-time major winner and former world number three, a wildcard in this tournament, was beaten 4-6, 6-4, 6-3 by 13th seed Borna Coric. Croatian Coric will face Klahn in the second round.
Others eliminated on Monday included ninth seed Diego Schwartzman, beaten 6-3, 6-4 by Sam Querrey, and 14th seed Milos Raonic, who lost 6-3, 5-7, 6-3 to qualifier Mackenzie McDonald.
Two more seeds made safe progress as Stefanos Tsitsipas (10th) and Marco Cecchinato (16th) saw off Gael Monfils and Gilles Simon respectively.
2016 finalist Roberto Bautista Agut, Marton Fucsovics, Andreas Seppi, Matthew Ebden, Taylor Fritz and wildcard Yibing Wu also advanced to round two.