Serena Williams has hit out at what she considers to be discrimination in U.S. Anti-Doping Agency's drug testing.
Williams posted on Twitter on Tuesday making it clear she didn't believe the process was a fair one:
As relayed by the Associated Press, it's not the first time Williams has discussed the issue. "Just test everyone equally," she said ahead of Wimbledon 2018.
Deadspin (h/t AP) reported in June that the 23-time Grand Slam champion had already been tested five times in 2018, which at the time was more than any top-five male or female tennis player from the United States.
Per the AP, USADA's "intelligent" testing initiative can lead to players who are more successful being tested more frequently.
While she was clearly unhappy, Williams did manage to make a joke with one Twitter user about the motives of USADA:
Williams returned to competitive tennis in early 2018 having missed the majority of the previous year because of pregnancy. She was forced to pull out of the French Open due to a shoulder problem, while she made it to the Wimbledon final but lost to Angelique Kerber.