Japan's Kei Nishikori has tested positive for COVID-19 while in Florida - just two weeks ahead of the US Open.
The 30-year-old former world number four has been staying at the IMG Academy in Bradenton, Florida.
The tennis star has pulled out of the upcoming Western & Southern Open, a warm-up tournament for many before the Grand Slam.
Taking to his app, he said he is "feeling well and has very little symptoms, but will obviously be in complete isolation for the safety of everyone".
Nishikori added that he will get tested again on Friday, before a decision on US Open status is taken.


Rutherford and Motie shine as West Indies sink England
Australia begin T20 World Cup with win over Ireland
Thomas Frank sacked by Tottenham
S Africa survive double Super Over drama against Afghanistan
Farhan fires Pakistan to 32-run win over US in T20 World Cup
