Alexander Zverev continued his quest for a second Grand Slam title of the season with a straight-sets triumph in his quarter-final match at the US Open.

The top seed eased past Dutch underdog Botic van de Zandschulp 6-2, 7-5, 6-1 without dropping his serve. Zverev spent just over two hours on the court to secure a new career milestone by reaching the last four of all Grand Slam events within the same year for the first time. He is also the oldest player in the Open Era to achieve this feat, doing so at 29.

“I think the more often that you get to that stage, the more normal it becomes, which is something that you should never take for granted,” Zverev said during his press conference.

“I don’t take it for granted at all. 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, and I found that out after Wimbledon where I didn’t play well throughout the two tournaments on the hard courts, and then I found it again here (at the US Open).”

Zverev’s route to the semi-finals has been far from easy, with the German dropping 80 games so far in the tournament. In the Open Era, the only top seed to have conceded more in New York was Rafael Nadal (85) in 2018.

In contrast, the player who has dropped the fewest games so far in the men’s tournament is Karen Khachanov, who is Zverev’s next opponent. The Russian, who has dropped 59 games, was leading Alexander Blockx 6-2, 7-5, 3-2 before the Belgian retired injured.

“He’s somebody that works extremely hard. He’s on the practice courts more than most people,” Zverev said of Khachanov.

“He’s always searching for solutions. He’s always trying to find new ways to get better. He has a great coach who I’ve known since the juniors. He’s been with him since juniors. That I respect a lot when people go together for a long time and go together a long way.”

Khachanov, who is 11 months older than the world No.2, has reached the semi-finals of a major for the third time in his career and the second at the US Open after 2022. He is currently ranked 50th in the ATP rankings but has been as high as eighth in the world. In this year’s draw, Khachanov has already beaten three seeded players – Felix Auger-Aliassime, Learner Tien and Blockx (via retirement).

“We call him (Khachanov) The Professor because he knows everything about tennis, and he knows every single string tension, knows what everybody does, so that’s quite fun,” Zverev commented.

“I’ve known him for many, many years, somebody that I grew up with playing junior tournaments. I have massive respect for him and I hope it’s going to be a great battle on Friday.”

Zverev will be the heavy favourite heading into the showdown despite a recent resurgence from Khachanov, who entered the US Open having lost five out of seven Tour-level matches played since the start of Wimbledon.

“He’s been in the top five for so many years. This year he also took a step forward. He won his first Grand Slam and played the Wimbledon final as well. He’s coming up really in hot form,” Khachanov said.

Zverev leads Khachanov 6-3 in their head-to-head.