Zhang Zhizhen sent fifth seed Casper Ruud crashing out of the US Open on Wednesday, creating tennis history by becoming the first man from China to beat a top-five player.

The 26-year-old from Shanghai – ranked 67th in the world – produced the match of his life to defeat last year’s US Open finalist 6-4, 5-7, 6-2, 0-6, 6-2 in 3hr 19min.

Zhang’s victory was the first time any male Chinese player has beaten a player ranked in the world’s top five.

Zhang will face Australia’s Rinky Hijikata in the third round on Friday, bidding to reach the last 16 of a Grand Slam for the first time.

Wednesday’s turnaround was in stark contrast to Zhang’s campaign in last year’s tournament where he was bundled out in the first round after his career was effectively shut down by the Covid-19 pandemic.

“First of all, with the COVID situation, it’s tough to get outside. Then everything is tough,” Zhang said.

“I don’t think (at) that moment we believed we can make this result. That moment I would say we are more thinking like try to break top hundred, that’s our goal, the goal you have step by step.”

Zhang said he would take that approach to the rest of the US Open starting with Friday’s third round tie.

“One round by one round, one step by one step, and we’ll see,” he said. “I can’t think too far. Every round is tough.”

Earlier, tempers had flared after Ruud had levelled the match at two sets apiece with a 6-0 fourth set.

Zhang left the court for several minutes to take a toilet break and change clothes in a move that clearly disrupted Ruud’s momentum.

The Norwegian was broken immediately in the first game of the final set, and a frustrated Ruud complained angrily at the chair umpire, accusing him of failing to enforce time limits.

“Why don’t you do anything?” Ruud yelled at the umpire. “You follow the rules clearly some times then other times you don’t give a shit. Why don’t you do anything?”

With Ruud unravelling, Zhang rammed home his advantage. He broke again in the fifth game to take a 4-1 lead and then held for a 5-1 lead.

Ruud held serve to close the gap to 5-2, but Zhang would not be denied, producing a superb backhand volley on match point to seal victory.

Ruud later admitted that Zhang’s lengthy break had derailed him before the deciding set.

“It’s six, seven minutes where I kind of walk around doing nothing,” Ruud said. “Lost my maybe groove there, and that’s frustrating, because you’re on a roll, you won the fourth set, you want to kind of keep going.

“That’s why I was a little frustrated, kind of asked the umpire about what the rules are here.”