WTA Tour chief Steve Simon defended Maria Sharapova's wildcard entry into the Stuttgart Open, pointing to other sports and their treatment of former dopers as an example.

After serving a 15-month ban for failing a drugs test, former world number one and five-time grand slam champion Sharapova will make her long-awaited comeback in Stuttgart on Wednesday.

Sharapova's return via a wildcard spot has angered her rivals, with Agnieszka Radwanska, Caroline Wozniacki and Roberta Vinci vocal in their disapproval, but Simon defended the Russian 30-year-old's return.

"You have to look at how other leagues and tours have handled players who have come back," Simon told BBC Sport.

"They come right back to the team and start playing."

"She is starting at ground zero," Simon added.

"It is going to affect her seedings in big tournaments so she's still going to pay a penalty for a while.

"If you think about it from other leagues, most of them [bans] are half of a season or a full season. She's had a year and a half."