Stefanos Tsitsipas denied bending the rules with his bathroom breaks during his dramatic five-set victory over Andy Murray at the US Open.

Scot Murray, 34, blasted the Greek third seed for the “nonsense” and said he had lost respect for him after Tsitsipas disappeared off court for almost eight minutes at the start of the fifth set.

However, after closing out a 2-6 7-6 (7) 3-6 6-3 6-4 victory over the 2012 champion in just less than five hours, Tsitsipas said: “If there’s something that he has to tell me, we should speak, the two of us, to kind of understand what went wrong.

“I don’t think I broke any rules. I played by the guidelines, how everything is. I don’t know how my opponent feels when I’m out there playing the match. It’s not really my priority.

“As far as I’m playing by the rules and sticking to what the ATP says is fair, then the rest is fine. I have nothing against him. Absolutely nothing.”

Murray’s defeat, and that of Marin Cilic, who had to retire at two sets all against Philipp Kohlschreiber, means there is only one player left in the men’s draw to have won a grand slam title – the 20-time major winner Novak Djokovic.

Daniil Medvedev, the second seed from Russia, got his bid for a maiden grand slam title off to a confident start by beating Richard Gasquet in straight sets.

The 25-year-old roared past Frenchman Gasquet 6-4 6-3 6-1 in less than two hours.

Nick Kyrgios won just seven games as his campaign came to an end at the hands of Roberto Bautista Agut.

Australian Kyrgios threw in his usual tweeners and underarm serves but Bautista Agut, the unflappable 18th seed from Spain, was too solid as he ran out 6-3 6-4 6-0 winner.

Andrey Rublev, the Russian fifth seed, is safely through after a straight-sets win over Croatian veteran Ivo Karlovic.

There was a surprise result in the men’s draw as wild card Brandon Nakashima defeated fellow American John Isner.

Nakashima upset 19th seed Isner, the American number one, 7-6 (7) 7-6 (6) 6-3.

Fellow seeds Ugo Humbert, Cameron Norrie and Alejandro Davidovich Fokina were also first-round casualties.