(Reuters) - U.S. Open 10th seed Kei Nishikori remains concerned over his fitness following a three-week injury break with the Japanese number one raising doubts about his prospects of making it past the first round in New York.
The world number 11 skipped warm-up tournaments in Toronto and Cincinnati after having a cyst removed from his right toe earlier this month and has just resumed training ahead of the final grand slam of the season starting next week.
