Alexander Zverev accuses Stefanos Tsitsipas of receiving mid-match coaching 

Before Alexander Zverev picked up his first Cincinnati title on Sunday, he first made it through a controversial semifinal battle against Stefanos Tsitsipas. Zverev overcame some audible frustration during the three-set bout when the Greek took an eight-minute bathroom break following the first set.

Tsitsipas left the court taking his entire bag, which triggered Zverev into an argument with umpire Adel Nour.

"He took his bag with his phone and everything in it," Zverev said to the chair umpire. "This was the same thing in Paris and is going to be the same thing every other tournament he's playing."

Zverev insinuated that Tsitspas would use his phone to receive illegal coaching advice from father Apostolos, who was immediately spotted texting in the stands.

Nour tried to assure Zverev that Tsitsipas was being escorted to the bathroom, but this failed to assuage the German.

"He's in the bathroom, he's not going to escort him into the toilet," Zverev responded.

When Tsitsipas returned to the court he was booed by the Cincinnati crowd, presumably for the long break, and Zverev was left trying to cool down from the heated exchange.

In Tsitsipas' post-match presser he addressed the situation and has no plans on changing up his routine in the future.

"I don't think it would be very nice if I change shorts on the court in front of everybody," Tsitsipas told press. "I prefer to do that in the locker room, including socks and shoes. I'm a person that sweats a bit more than others. I think it's acceptable. Some people were teasing me and making fun of this, but it's just how it works for me.

"People have to understand. I'm not going to stop doing it, because it makes me feel better when I step out on the court to begin the new set."

Zverev’s coaching allegations were not addressed in either post-match press conference.

After emerging victorious, 6-4, 3-6, 7-6(4), avenging his Roland Garros defeat, all frustrations were seemingly put to the side as Zverev shook hands with Tsitsipas at net and wished him the best at the US Open.