Alexander Blockx retires against Karen Khachanov in US Open quarter-finals

Retirement on Arthur Ashe

Belgian 21-year-old Alexander Blockx retired from his maiden Grand Slam quarter-final against Karen Khachanov on Wednesday evening in New York. The 28th seed, ranked 34th in the world, conceded the match after 1 hour and 38 minutes of play on Arthur Ashe Stadium while trailing 6-2, 7-5, 3-2. Blockx struggled physically from the warm-up, dealing with lingering rib pain before suffering a pinched nerve in his back during the second set. He requested a medical timeout for a blister after the opening set and received further treatment on his back after the second set, before retiring when Khachanov broke his serve in the fifth game of the third set.

I think my body just gave up today. I was still feeling a lot of pain around the ribs. I felt my leg as well. And, in the second set, a nerve in my back locked up.

Physical toll of deep Grand Slam run

Blockx entered the quarter-final carrying physical fatigue from his fourth-round match against 24th seed Francisco Cerúndolo. In that round-of-16 contest, the Antwerp native required medical attention for right intercostal pain during a battle lasting over three hours before advancing in four sets (6-3, 4-6, 7-5, 7-5). Although painkillers allowed him to finish against Cerúndolo, the accumulated physical strain restricted his movement against Khachanov. Blockx stated after the match that playing in Arthur Ashe Stadium provided the primary motivation to step onto the court despite the pain.

The only reason why I stepped on the court is because I realize how rare it is to have the opportunity to play in Arthur Ashe Stadium.

Milestone tournament and rankings rise

Despite the mid-match retirement, Blockx achieved several career milestones during his debut appearance at the US Open. He became the first Belgian man to reach the quarter-finals at Flushing Meadows, as well as the youngest Belgian in the Open Era to reach the last eight of a Grand Slam tournament. Earlier this season, Blockx reached the semi-finals at the Madrid Masters 1000. His quarter-final run in New York will elevate him into the ATP top 30 for the first time when the updated rankings are published on Monday. The physical setback is expected to rule him out of Belgium's upcoming Davis Cup tie in Austria next week.

Semi-final lineup at Flushing Meadows

Khachanov, ranked 50th in the world, advanced to his second US Open semi-final following his 2022 run. He will face world number two and top seed Alexander Zverev, who advanced after defeating Dutchman Botic van de Zandschulp. The opposite side of the draw features an all-American semi-final between eighth seed Ben Shelton, ranked ninth, and 11th seed Frances Tiafoe, ranked 12th. In the women's doubles draw, Belgium's Elise Mertens and her partner Diana Shnaider exited in the semi-finals after a 6-0, 7-6 (10/8) defeat against top seeds Katerina Siniakova and Taylor Townsend.