Serena Williams says she would have been banned for 20 years had she committed a doping offence similar to that of men's player Jannik Sinner.

Williams admitted that Sinner’s situation made her reflect on the experience of Maria Sharapova, a long-time rival on the court. Sharapova had a two-year ban reduced to 15 months on appeal in 2016 after testing positive for meldonium, with Cas finding that she bore "no significant fault" for ingesting the substance.

Sinner is serving a three-month suspension that expires on 4 May after returning two positive tests last year.