Maria Sharapova returns after 15-month doping ban

All eyes will be on the Russian on the day she is eligible to compete again - her first appearance on the WTA Tour since reaching the quarter-finals of last year's Australian Open, when she tested positive for meldonium.

The former world number one, who won Wimbledon in 2004, admitted taking the cardiac drug last March, insisting her only mistake was not realising the substance had been added to the banned list at the start of 2016.

Asked if she expected the suspicion to linger for the rest of her career, Sharapova told Vogue last month: "I think if I was trying to hide something, I don't think I would come out to the world and say I was taking a drug for 10 years.

"If I was really trying to take the easy way out, that's not a very smart thing to do. But the answer to your question is, absolutely."

Sharapova is a three-time winner in Stuttgart, triumphing in 2012, 2013 and 2014, but the build-up to her return to the tour means she will not be able to take a warm welcome from the crowd for granted.

As she has had her ranking suspended until her ban, reduced from two years on appeal, expires, the 30-year-old has had to rely on a wild card to compete at this week's Porsche Grand Prix in Stuttgart.

The Madrid and Italian Opens have followed suit with wild cards, and the decision to accommodate the five-time grand slam champion automatic entry to events she would otherwise not qualify for by ranking has drawn the ire of several prominent professionals.

Former world number one Caroline Wozniacki said last month the wild cards were "disrespectful" to other players, while Agnieszka Radwanska suggested Sharapova should not be invited to grand slams.

Andy Murray, a noted hard-liner on anti-doping, said in the Times last month: "I think you should really have to work your way back."

Even her opponent on Wednesday, Italy's Vinci, joined the chorus, saying in The Times: "My personal opinion is that I don't agree about the wild card here and about the wild card in Rome and the other tournaments.

"She made her mistakes for sure, but she paid (for it) and I think she can return to play, but without any wild cards."