Alexander Zverev took another big step towards a second Grand Slam title by beating Dutchman Botic van de Zandschulp 6-2 7-5 6-1 to reach the U.S. Open semi-finals, where the German will take on Karen Khachanov.
The 29-year-old French Open champion got off to a slow start in his campaign at Flushing Meadows but has steadily found his range. "I think you saw in the first two rounds, I really didn't play well," Zverev said.
"In other tournaments I would be out in the first round, but here I can fight back and play best of five sets, play 4-1/2 hours. I've started playing better throughout the tournament and I'm definitely happy to be in the semi-finals here."
The German has reached the semi-finals at all four majors this year and is the only Grand Slam winner left standing in the men's draw. "I don't take it for granted at all," Zverev said. "I know it can change in a heartbeat in tennis. I think confidence is something that is incredibly important but also can go away quite quickly."
Zverev was far from steady on serve early on at Arthur Ashe Stadium, coughing up five double faults in an erratic start, but van de Zandschulp leaked forehand errors to allow the top seed to break in the fifth game and then take the first set.
Van de Zandschulp regrouped in the second set and came close to levelling the contest, but Zverev absorbed the pressure and reeled off three games in a row towards the end as the momentum swung firmly in the German's favour.
Zverev, the 2020 runner-up, fired an overhead smash to break early in the third set and cruised home from there to reach his third semi-final in New York. With 23 Grand Slam match wins this year, Zverev surpassed Boris Becker's German men's record of 22 from 1989.
He next faces Russian Khachanov in a rematch of their gold medal showdown at the Tokyo Olympics in 2021. Khachanov advanced to the semi-finals when Alexander Blockx retired trailing 6-2 7-5 3-2, as the Russian reached the final-four stage in Flushing Meadows for the first time since 2022.
Blockx, who became the first Belgian man to reach the U.S. Open quarter-finals, was already carrying a rib injury into the match and was visibly hampered by further physical issues. He wore a brace on his right ankle and had his thigh wrapped, with the 21-year-old also calling for the trainer during the contest.
The 28th-seeded Blockx battled on despite his discomfort but was unable to match Khachanov as the 30-year-old continued his resurgence in New York, before eventually calling it a day after one hour and 38 minutes. Blockx, who upset fifth seed Flavio Cobolli in the third round, had already hinted at his physical issues, admitting he came close to retiring during his match against Francisco Cerundolo in the fourth round.
"Today my body just gave up," Blockx told reporters. "I had it really difficult physically already. Against Francisco, I was on the verge of retiring, and today just kept getting worse."
"I was still feeling my rib a lot. My leg. Then in the second set, I blocked a nerve in my back, which yeah, was even worse to move."
World number 50 Khachanov will return to a Grand Slam semi-final for the first time since reaching the last four at the Australian Open in 2023. "I was preparing really well for that match up, it's not easy because I feel I was dominating then I felt he was struggling more and more," Khachanov said on court.
"He was suffering, but I wanted to keep the energy there. I wish him a speedy recovery but I'm super happy I'm in the semis." The former world number eight, who had not played a major with a ranking this low since 2017, had already knocked out third seed Felix Auger-Aliassime and 14th seed Learner Tien on his way to the last eight.
