The tennis world was rocked with the news World No.2 Daniil Medvedev was sent into isolation after testing positive for the coronavirus, but concerns also grow for Nadal after footage of him training with the Russian emerged.
Medvedev, who was runner up to Novak Djokovic at the Australian Open earlier this year, had completed a practice session with Spain's Rafael Nadal prior to his positive test.
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While Medvedev's health is being monitored in isolation, fans have expressed concern for Nadal after footage emerged of their practice session.
Leading tennis reporter Jose Morgado posted a video of the footage and the account, We Are Tennis, reposted with the caption: "Oh God."
Many other fans expressed their concern after seeing the footage.
Nadal allowed to practice after scare
Despite the concern, Nadal was not considered a 'close contact' of Medvedev, according to Morgado.
This allowed Nadal to practice on Wednesday ahead of his second round clash at the Monte Carlo Open.
Nadal has since returned a negative test after contact with Medvedev, but his camp will wait for him to be tested again in three days for him to be given the all-clear.
Medvedev, who was seeded second behind top-ranked Novak Djokovic at the ATP Masters 1000 event on clay, has been put in isolation and is being monitored by the tournament and ATP medical teams, the men's tennis governing body said in a statement.
"It's a big disappointment not to play in Monte-Carlo," Medvedev said.
"My focus is now on recovery and I look forward to getting back out on Tour as soon and as safely as possible."
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