Kei Nishikori is the latest top player to pull out of the U.S. Open because of an injury.
The agent for the 2014 runner-up and 2016 semifinalist at Flushing Meadows said Wednesday that Nishikori will miss the rest of the season because of a torn tendon in his right wrist.
Olivier van Lindonk wrote in an email that Nishikori, who is No. 9 in the ATP rankings, heard a ''pop'' in his wrist while hitting a serve during a practice session this week at the Western & Southern Open hard-court tournament in Mason, Ohio. Nishikori withdrew from that event on Monday.
Van Lindonk said Nishikori saw two wrist specialists and sent results of MRI exams to three other wrist doctors before deciding to end his season.
Nishikori has chosen not to have an operation on his wrist ''at this stage,'' according to Van Lindonk. Nishikori will wear a cast on his wrist and, after the swelling reduces in the coming weeks, ''we will evaluate next steps,'' Van Lindonk said.
Nishikori joined defending champion Stan Wawrinka and three-time winner Novak Djokovic in deciding to sit out the U.S. Open, which starts Aug. 28.
Wawrinka had surgery on his left knee, while Djokovic has a problem with his right elbow. Like Nishikori, both are out for the rest of 2017. That trio represents three-fourths of last year's semifinalists at Flushing Meadows; the other was Gael Monfils.
At the 2014 U.S. Open, Nishikori became the first man from Japan to reach a Grand Slam final, losing the championship match to Marin Cilic. Nishikori advanced to his second major semifinal in New York a year ago, before losing to Wawrinka.
Nishikori has repeatedly dealt with injuries during his career, although he has managed to be ready for Grand Slam tournaments, participating in 21 in a row until now. The last major he missed was the 2012 French Open.
Nishikori ends 2017 with a 30-13 record and two appearances in tournament finals.
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