Prof Jie Jin Wang, an expert in vision research at Sydney University in Australia, said this was something doctors might want to discuss with high-risk patients.

BBC: Long-term aspirin 'blindness link'

Sharapova had not played since losing to China's Zheng Jie at Indian Wells and her lack of match practice after an elbow injury showed in a 6-4 6-3 defeat at Caja Magica.

CNN: Sharapova and Henin crash out in Madrid