Kei Nishikori advanced to the second round of the U.S. Open on Monday after Marco Trungelliti retired with an injury in the second set of their match.
The seventh-seeded Nishikori had a trouble-free start to his campaign for a first Grand Slam title as he took the opening set off Trungelliti 6-1, and was up 4-1 in the second set when the Argentine qualifier retired, 47 minutes into the match.
“What I want most right now is confidence,” Nishikori said.