Andy Murray was left fuming after his five-set loss to the Greek star and said he had "lost respect" for him after he took long bathroom breaks at pivotal moments. Muray used the word "cheating" on court. The 34-year-old Brit suggested it "can't be a co-incidence" that the breaks were taken at times where the momentum was with Murray.
The incident sparked debate across the tournament about how long players really need during bathroom breaks and whether the rules should eliminate any attempts of gamesmanship from competitors.
After his 6-4, 7-5, 6-2 first round win over American Sam Querrey, Zverev teed off on Tsitsipas, saying he had experienced similar tactics just over a week ago.
"It's happening every match. It's not normal," said Zverev.
"It happened to me in the French Open, to Novak (Djokovic) in the finals at the French Open. You know, I think in Hamburg against (Filip) Krajinovic he was complaining, against me in Cincinnati was ridiculous, and now here again. I think players are catching up on that."
Zverev was in a similar position against the Greek player in the semi-finals of the Cincinnati lead-in tournament. After winning the first set 6-4, Tsitsipas took his bag into the bathroom with him, presumably to change into dry clothes. However, that set off alarm bells for Zverev who accused Tsitsipas of taking his mobile phone in as well and texting with his father/coach Apostolos, which is in breach of ATP rules.
Tsitsipas denied that he's ever done anything like that when asked after his win over Murray, but Zverev was having none of it following his victory this morning AEST.
"He's gone for 10-plus minutes. His dad is texting on the phone. He comes out, and all of a sudden his tactic completely changed," Zverev said. "It's not just me but everybody saw it. The whole game plan changes.
"Either it's a very magical place he goes to or there is communication there. But I also don't want to disrespect him. He is a great player. He is No.3 in the world for a reason. He's winning tournaments and playing incredible tennis this year for a reason, so it's not only that. But I do believe, and Andy said it, as well, there is some level of respect that everybody needs to have between players.
"I feel like, yeah, sometimes – or he might just go to the toilet. We don't know that. That's also possible. But it just happens too often, I would say."
Murray couldn't let it go and doubled down on his criticism of Tsitsipas on social media, telling his followers: "Fact of the day. It takes Stefanos Tsitipas twice as long to go the bathroom as it takes Jeff Bezos (sic) to fly into space. Interesting."
Even though Tsitsipas' conduct has raised the ire of rivals, the No.3 seed has some support.
American tennis player Reilly Opelka defended Tsitsipas and said he "highly doubts" the star is being coached during bathroom breaks at crucial moments.
Opelka, the No.22-seeded male, who swept past Soon-woo Kwon in the first round, admitted he has no connection to the Greek star but felt the need to defend him because the "tennis media sucks".
"I think it's ridiculous. I understand it's getting press because tennis is lame and tennis media sucks and they're terrible," Opelka said during his post-match press conference.
"It's hot and humid, and for the media, the press that have never stepped foot on a tennis court in their life, have never been in the environment, couldn't last 30 minutes out in this humidity, in this heat. It's physical, our sport is. My shoes are dripping, they're leaking sweat.
"To change or to go after, you know, two sets we're drinking, we're hydrating a lot, we have to use the bathroom.
"To change socks, shoes, my inserts in my shoes, shorts, shirts, everything, the whole nine yards, hat, it takes five, six minutes.
"I don't know Tsitsipas, I don't know his situation, I doubt he's getting coached. I highly doubt it. Today I couldn't even take my bag in to change. I'm like, guys, my clothes and shoes are in here. You can come in and stand with me if you want."
Article I, Section W, Paragraph 4 of the 2021 Grand Slam rule book limits women (who play best-of-three-sets) to one trip off court and men (best-of-five) to two trips "for a reasonable time for a toilet break, a change of attire break, or both."
Murray is among those who have advocated for some sort of rule switch by stating how much time players should have. He called for harsher consequences than the simple warning that Tsitsipas received from the chair umpire for a time violation, when both players were hit hard by conditions.
Even one of the game's legends questioned how open-ended the rules are and said there is room for players to break them.
"It's so vague. Another vague rule in tennis. And I think that's what Andy was complaining about," 18-time major champion Chris Evert said during ESPN's telecast Tuesday.
"Let me tell you, eight to 10 minutes, that gives the player time to sit with himself, to figure out what he needs to do, to reset if he needs to, to reach into his bag and get a phone call. Or reach into his bag and read a text. It opens the door to a lot of things that maybe aren't fair in tennis."
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