Daniil Medvedev has become the latest player to cast doubt over participation at the Australian Open in January.

Current US Open champion Medvedev refused to disclose his vaccine status on Sunday, saying he preferred to keep his medical records private.

The Russian’s move is similar to that of world No.1 Novak Djokovic.

“I always said it, that I really like Novak’s answer about this. I want to keep my medical, no matter if it’s about vaccine, leg injury, head injury… I want to keep my medical private for a reason,” Medvedev said.

“I feel like tennis is such a brutal sport where you’re always one on one against your opponent, and any information you give him can go against you.

“If you’re playing Australia, it’s obvious you’re vaccinated. So that’s why I said I’m willing to play Australia, but I won’t say if you’ll see me there, but we’re going to see in January.”

Medvedev was joined in Paris for the Masters tournament by Djokovic, who said he would wait for Tennis Australia to confirm what the rules will be on quarantines and vaccinations before he making his decision.

“Right now we don’t have any official announcement or statement,” Djokovic said. “So until that’s out, I won’t be talking about this anymore.”