Tennis-Alcaraz retires to send Auger-Aliassime into US Open semi-finals

Felix Auger-Aliassime moved into the U.S. Open semi-finals on Tuesday when Spanish teenager Carlos Alcaraz retired while trailing 6-3 3-1. The 18-year-old Spaniard showed no signs of distress as Auger-Aliassime took the opening set but after the Canadian broke to open the second Alcaraz slumped.

Felix Auger-Aliassime moved into the U.S. Open semi-finals on Tuesday when Spanish teenager Carlos Alcaraz retired while trailing 6-3 3-1.

The 18-year-old Spaniard showed no signs of distress as Auger-Aliassime took the opening set but after the Canadian broke to open the second Alcaraz slumped. With Auger-Aliassime building a 3-1 advantage and Alcaraz preparing to serve, the Spaniard turned and indicated he could not go on.

"I don't know what happened, I didn't see it coming," Auger-Aliassime in an on court interview. "I thought we were putting on a good show." Coming off gruelling back-to-back five-set matches, including a third-round win over Stefanos Tsitsipas, Alcaraz stepped onto the court with both legs heavily strapped and seemed to lack the power and energy that had carried him to the quarter-finals.

The retirement sends Auger-Aliassime into the semi-finals, the same stage as compatriot Leylah Fernandez, who booked her spot in the women's last four earlier in the day by beating Elina Svitolina.