US tennis star Serena Williams has suggested discrimination is the reason behind the frequency with which she is selected for anti-doping tests.
...and it’s that time of the day to get “randomly” drug tested and only test Serena. Out of all the players it’s been proven I’m the one getting tested the most. Discrimination? I think so. At least I’ll be keeping the sport clean #StayPositive
— Serena Williams (@serenawilliams) July 25, 2018
"...and it's that time of the day to get 'randomly' drug tested and only test Serena," she wrote on Twitter Wednesday. "Out of all the players it's been proven I'm the one getting tested the most. Discrimination? I think so. At least I'll be keeping the sport clean #StayPositive."
In a second message she then wrote: "But I'm ready to do whatever it takes to have a clean sport so bring it on. I'm excited."
Williams, 36, had been tested five times by the United States anti-doping agency (USADA) in 2018, up to July 20, according to its online database. In tennis only doubles specialist Bob Bryan (four) and John Isner (three) had been tested more than twice in the same period.
The 36-year-old Williams, a 23-time grand slam champion, is making her comeback this year having given birth last September.
Williams had previously complained about the frequency she was tested during her run to the Wimbledon final earlier this month. The website Deadspin had revealed the comparatively high number of tests she had undergone in the first half of the year.