Alexei Popyrin has joined newly-crowned Atlanta Open champion Alex de Minaur in the second round of the Citi Open in Washington after his first-round opponent retired mid-match.
The scores were level at 3-3 in the first set on Monday when Taiwan's Wu Tung-lin called a halt.
Popyrin next faces a big test against in-form American third seed Taylor Fritz, who had a first-round bye.
De Minaur also enjoyed a bye, giving him more time to rest after his title triumph in Atlanta before a possible rematch with American Jenson Brooksby, the player he beat in straight sets in Sunday's final.
Brooksby must first get past Japan's Yoshihito Nishioka.
Also preparing for the US Open, Wimbledon finallst Nick Kyrgios will attempt to join Popyrin and de Minaur in the second round when he takes on American Marcos Giron in their first round-clash.
Fellow Australian James Duckworth was ousted in the first round, losing to Croatia's Borna Gojo 4-6 7-6 (7-4) 6-2.
Former world No.1 Andy Murray lost his opening match 7-6 (8-6) 4-6 6-1 to Swede Mikael Ymer. Murray started cramping at the end of the first set and struggled to recover.
"It was disappointing, obviously," Murray said." I thought there was some good tennis in the first set. After that, both of us were struggling a bit physically. The level of the tennis was not great."
with The AP
