Rafa Nadal's coach has speculated whether Novak Djokovic's decision to remain unvaccinated could hurt his ambition to finish atop the men's grand slam leadership board.
Former World No.1 Carlos Moya, who took over as Nadal's coach after Uncle Toni, was with the Spaniard at the Australian Open as he lifted a men's record 21 grand slime titles.
Nadal prevailed in what has been described as the 'greatest comeback' in the Open Era to defeat Daniil Medvedev 2-6, 6-7 (5-7), 6-4, 6-4, 7-5 in the final.
Much of the talk leading up to the Australian Open was Djokovic's absence and how it will affect his bid to overtake Nadal and Roger Federer on the leaderboard.
And with Nadal's remarkable 21st title, the debate took on a new life with reports claiming Djokovic could have changed his mind and is considering getting vaccinated to compete.
Now, Nadal's coach has discussed how it could impact Djokovic's charge.
Moya does not think Djokovic is anti-vaccination, but claimed Djokovic's career could be in 'serious danger'.
"I don't think Rafa's win will have changed anything in his mind," Moya told Spanish radio station Onda Cero.
"But it's clear that if he doesn't get vaccinated then he's going to fall behind in the battle he has fought so long for.
"I think it's going to be very difficult for him to compete in grand slam tournaments if he doesn't get vaccinated, and his career will be in serious danger."
Moya went on to praise Nadal and said he was able to 'control his nerves' when down two sets against Medvedev in the Australian Open final.
Djokovic is facing uncertainty over competing in grand slams if he remains unvaccinated with doubt cast over Roland Garros and Wimbledon, while the US Open remains unlikely as the law stands right now.
Rafa Nadal and Roger Federer announcement
Last week, Federer made the huge call and confirmed his intention to play at the Laver Cup this September, along with Nadal.
Tennis fans remember the iconic scenes when 'Fedal' teamed up to play doubles together at the first edition of the Laver Cup.
And with both players in the twilight of their career, fans couldn't be more excited for one last chance to see the two legends on the same side of the court.
While the next edition of the tournament is still later this year, to be held in London from September 23-25, Federer has signalled the tennis tournament is part of his plans.
"I'm really looking forward to getting back into competition later this year and Laver Cup is very much part of my plan," Federer said.
"It's no secret that I love the event and I'm super excited to be returning to The O2 and to London, one of the greatest cities in the world."
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