Top seed Alexander Zverev reached the US Open semifinals after defeating Botic van de Zandschulp in straight sets by 6-2, 7-5, 6-1 on Wednesday. This was the German’s 51st win of the ongoing season, which is the most for any player.

Furthermore, he has 23 major wins this season, which is the most by a German man in a single season, surpassing Boris Becker’s 22 in 1989.

“Happy to be in the semi-finals,” Zverev said in his post-match press conference. “Different kind of match than two days ago, but still happy to win in straight sets and to move on.”

This will be the 13th Slam semi-final for Zverev, which is the second-most among active male players (Novak Djokovic, 55).

With this win, Zverev became the ninth different man in the Open Era to reach the semi-finals at all four majors in a season.

“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. “I think it’s a very special feeling when it becomes a normal thing. I don’t take it for granted at all… I’m happy with how things are going, but looking forward, I still hope to play two good matches in New York.”

Zverev will face Karen Khachanov in the semifinals of the New York Major. Khachanov made it to the semis after Alexander Blockx decided to retire due to a rib injury.

“I was preparing really well for this matchup and it was not easy, as from one side I felt like I was dominating from the beginning and then I felt he was struggling more and more and it is a mixed feeling,” Khachanov said. “He is suffering and I don’t want to scream, ‘Come on’, but I wanted to keep the energy there. I wish him a speedy recovery. I saw that he was suffering all over his body.”

Zverev has a 6-3 record against Khachanov.