Daniil Medvedev has withdrawn from the Monte Carlo Masters after testing positive for Covid-19, the ATP Tour announced on Tuesday, raising questions about the latitude afforded to Monaco residents like the Russian who are allowed to stay at home rather than in a bio-secure hotel.
"It's a big disappointment not to play in Monte-Carlo. My focus is now on recovery and I look forward to getting back out on Tour as soon and as safely as possible," the world number two said in an ATP statement.
Medvedev tested positive on Monday having practised with Rafael Nadal the day before.
Organisers, contacted by AFP, declined to comment on whether the third seed risked being identified as a 'close contact' of Medvedev and forced to quarantine, scuppering the Spaniard's quest for a 12th Monte Carlo title.
Medvedev went into isolation following the test result "and continues to be monitored by the Tournament Physician and ATP Medical Team", the statement added.
The finalist in Monte Carlo in 2019 had a first round bye and has been replaced in the singles second round where he was due to play either Fili or Nikoloz Basilashvili on Wednesday.
As a Monaco resident, like Novak Djokovic, the 25-year-old was allowed to reside at his home, in contrast to other players who are living in strict bio-secure bubble accommodation in an official hotel and only allowed to leave to go the the Monte Carlo Country Club.
"I'm very lucky to be able to stay at my home this week, it's nice in this period of 'bubbles'," he said at the weekend.
World number one Djokovic echoed Medvedev's words on the comforts of home living but emphasised that he still followed the tournament's hygiene protocol by not going out.
He said he had delayed entering what he termed the event's "safe environment" until Sunday, so as "to remain free" and go wherever he wanted.
Players staying at their own homes are subject to daily coronavirus tests while those in the hotel are tested every couple of days.
Medvedev, runner-up to Djokovic in the Australian Open this year, took over the number two ATP ranking with victory at Marseille in March.
He was due on court in Monte Carlo following his upset quarter-final loss to Spaniard Roberto Bautista Agut in the Miami Open at the start of the month.
Nadal opens against Federico Delbonis on Wednesday.