'Case closed': Rafael Nadal backs 'innocent' Jannik Sinner as return from doping ban looms

The countdown for Jannik Sinner's return to the professional circuit may be nearing its end but two stars of the game fear the tennis world has not moved on from his ban.

Sinner has not taken to the court since claiming the Australian Open title in January as he accepted a three-month ban for two positive doping tests.

The handling of the 23-year-old's doping case was criticised by many past and present players with Sinner's ban ruling eligible to return in time for Roland-Garros.

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Serena Williams is the latest great to question the consistency in handling of doping cases, insisting she would have been hit with a 20-year ban had she been in a similar situation to Sinner.

"I've been put down so much, I don't want to bring anyone down," she told Time Magazine when asked about Sinner's case.

"But if I did that, I would have gotten 20 years. Lets be honest, I would've gotten grand slams taken away from me."

Williams admitted she "can't help but think" about Maria Sharapova's doping ban when top ranked stars are placed under investigation as her former rival was forced to serve a two-year suspension after unintentionally taking a performance enhancing drug.

Sinner was allowed to return to training last week and is set to make his first appearance since the ban at the Italian Open in Rome on May 6.

While perceptions around his return will likely remain a mixed bag, Rafael Nadal believes it is time everyone comes to accept the ruling that was made.

"In the end, if I'm not mistaken, he came out of the ruling as innocent," Nadal told the UK Telegraph.

"In this case it's not been positive for our sport but these things happen sometimes.

"Accidents happen and that's how I see this because I believe in Jannik.

"I'm convinced from what I know of Jannik that he never tried to cheat or get an advantage over the rest. I am sure that Jannik is an innocent and moral person.

"I don't want to put in doubt the ruling. There are protocols that we've all followed for our careers. If we don't like how the protocols function then evidently the people involved need to work to improve them. I believe in the ruling.

"Jannik has accepted these three months of sanction and so case closed."

British No.1 Jack Draper also jumped to the defence of his close friend and declared that he "does not deserve the hate" that he has been subject to.

"When people ask about Jannik I tell the truth - I think he is a really genuine, nice person and on top of that he is an unbelievable player," Draper told the BBC.

"In this situation I am sure he would have had absolutely zero idea of anything.

"That's the way life goes - sometimes there are mistakes.

"I think it is important for people to know and recognise the guy is kind-hearted and a good human being.

"He doesn't deserve any of the hate he gets"