Maria Sharapova, who tested positive for meldonium—a banned substance—at last year’s Australian Open, has received wild cards into Stuttgart, Madrid and Rome this year.

That doesn’t sit well with Andy Murray, who believes that those convicted of doping should have to start from the bottom and work their way up, and not be given any preferential treatment.

"I think you should really have to work your way back," the world No. 1 told London’s The Times. "However, the majority of tournaments are going to do what they think is best for their event. If they think having big names there is going to sell more seats, then they're going to do that."

And Sharapova, despite not having played a tournament in over a year, is still one of the biggest names in the sport. A five-time Grand Slam champion and former world No. 1, the 29-year-old Russian remains a major attraction and will unquestionably sell tickets.

If Sharapova plays well ahead of Wimbledon, which begins on July 3, she could earn enough ranking points to qualify for the main draw at the All England Club. She’ll need to receive a wild card to play the French Open, though.

“[Sharapova] has an opportunity to try to improve her ranking up until that point, and potentially not need a wild card," Murray told the newspaper. “But then if she doesn't, that becomes Wimbledon's decision, and how they want to play that. I'm sure they'll think long and hard about it, and how they feel people will view it, and then make the right decision for them.”

Sharapova was suspended two years by the International Tennis Federation in June for her positive test. That suspension was later reduced to 15 months.

She’ll return to the WTA tour in late April, in Stuttgart.