Japanese tennis star Kei Nishikori is doubtful for next week’s US Open after once again testing positive for the deadly novel coronavirus.

Confirming the news, the 30-year-old former world No.1 said that he recently undertook another COVID-19 test which returned with positive result.

Nishikori further revealed that he currently has minimal symptoms of the virus and that he is staying in full isolation in Florida.

“Just a little update, I just took another COVID test and am still positive. I have very minimal symptoms and am staying in full isolation in Florida,” Nishikori said in his official website.

Nishikori also confirmed that he will now undergo another coronavirus test early next week.

“The next test will be early next week at which time we will update you with more information,” he added.

Last week, the 2014 US Open runner-up withdrew from the Western and Southern Open in Cinicinnati after first being diagnosed with the novel virus.

Earlier, Switzerland’s Belinda Bencic, Australian tennis star Nick Kyrgios, 2019 US Open champion and current world number two Rafael Nadal, world No.1 Ashleigh Barty, defending champion Bianca Andreescu all withdew from the Flushing Meadows tournament due to coronavirus fear.

The US Open, which will be the first Grand Slam of the year for players amid coronavirus,is slated to take place from August 31 to September 13.