DELRAY BEACH, Fla. (AP) Defending champion Sam Querrey of the United States began his Delray Beach Open title defense Monday with a victory over Dudi Sela of Israel.
Querrey, the No. 4 seed, was leading 6-2, 2-1 when Sela retired. Querrey, who is ranked 35th in the world, advanced to a second-round match with either Jared Donaldson or Mikhail Kukushkin.
Last year, Querrey beat Rajeev Ram in the Delray Beach final for his first ATP World Tour title since 2012.
No. 8 seed Kyle Edmund of Great Britain also advanced Monday with a 6-3, 6-0 triumph over Adrian Mannarino of France. Edmund next plays Yen-Hsun Lu, who came from behind to beat Bjorn Fratangelo 4-6, 7-5, 6-4.
Yoshihito Nishioka of Japan won his first-round match 6-3, 6-3 over qualifier Kimmer Coppejans of Belgium. Nishioka will next face either No. 5 seed Steve Johnson or Stefan Kozlov.