TOKYO -- Kei Nishikori says he will sit out Japan's Davis Cup quarterfinal against the Czech Republic this weekend due to a groin injury.
Nishikori has retired or withdrawn 14 times in his career, including three times in Grand Slam events. He said he won't need surgery, but he's unsure how long he'll be sidelined.
Nishikori's absence hurts Japan's chances of beating the two-time defending champion Czechs in their first tie since 1935.
Go Soeda, scheduled to be Japan's No. 1 in Nishikori's absence, came down with a fever and also will not play Friday.
In addition, the Czech team will be missing its top player after Tomas Berdych withdrew following two tough tournaments in the United States.
The Associated Press contributed to this report.