Stefanos Tsitsipas has returned serve to Andy Murray as the controversy over the Greek star's lengthy bathroom breaks rumbles on two days after the former world No.1 said he'd "lost respect" for the 23-year-old.
After the pair's epic five set first round clash, Murray lit a fire that has caught hold throughout the tennis world by calling Tsitsipas out for disrupting play, first with a medical time-out, then with an eight-minute bathroom break at the end of the fourth set that had the three-time grand slam winner fuming.
Tsitsipas again raised eyebrows in his second round match today, this time taking a seven-minute stoppage during his four set win over Frenchman Adrian Mannarino.
While Tsitsipas hasn't broken any rules with his lengthy stoppages over the course of this week's US Open, he was forced to defend himself during today's press conference after fielding a number of hard-hitting questions by journalists.
"I would like to know what is the rule?" Tsitsipas replied when questioned about today's break.
"The rules are there to be followed.
"If I break the rules, sure I'm guilty, I agree. If I'm staying within the guidelines then what's the issue?"
Pressed again on the issue and whether he understood Murray's criticism surrounding the ethics of the sport, Tsitsipas hit back by bringing up the 2012 US Open final, in which Murray took a bathroom at the end of the fourth set of his clash with Novak Djokovic. Murray went on to win the fifth set and the championship after stopping the Serbian's momentum when the match was squared at two sets apiece.
Tsitsipas went into a back and forth with a reporter over the matter.
Tsitsipas: I have a question for you. I don't watch other people's business. But I remember watching it when I was younger. Can you please check when Andy Murray faced Novak Djokovic at the final here, before the fifth set, that break, can you please look it up and let me know next time?
Reporter: I did. He took less than three minutes.
Tsitsipas: Less than three minutes, okay.
Reporter: I looked it up.
Tsitsipas: Okay. So three minutes more make a difference?
Reporter: He thought so. It's a question of clearly you're doing something that is upsetting your peers.
That point was backed up by American Sloane Stephens, who said the issue of lengthy bathroom breaks is also evident in the women's side of the sport. The former US Open champion added that a change to the rules would be a welcome sight.
"I do know on the girl's side, there still is a lot of that," Stephens said.
"It's gamesmanship. I think there definitely needs to be a rule or changes. They make a lot of rule changes for smaller things - like they took one minute off the warmup.
"If someone goes to the bathroom for nine minutes, no one says anything."
After hearing the exchange between Tsitsipas and the reporter, former Australian tennis star Darren Cahill, who is now one of the most highly regarded coaches on the tour, disagreed with the "narrative" Tsitsipas was spinning.
He said the people calling Tsitsipas out were qualified to have an opinion, given they were mainly players and ex-players.
"That's the wrong narrative, he shouldn't be going down that path," Cahill said.
"That's not correct. We as former players are saying it's too long.
"We do know what it's like to go through what he's going through, maybe not as his level, but there are much better players than me that have commented on this and eight minutes is too long to change your clothes and go to the bathroom.
"He's right, he's not doing anything wrong. He's not going against the rules.
"The rules basically say you can take a bathroom break or a change of clothes break within a reasonable time.
"Now what is a reasonable time? This is where the sport lets down the players and the sport needs to be more authoritative with this and set a time limit.
"Here at Arthur Ashe Stadium, the bathroom is 10 steps off the court. You can go in there, get your clothes off, change your clothes and be back on the court within two or three minutes no problem.
"So, set whatever time you want and the players will go by it.
"Once you go over that time, you get a warning for a time delay and every 30 seconds after it you get docked a point and I promise you the players will get back on the court in time."
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