Serena Williams calls anti-doping system ‘grueling’ ahead of Wimbledon return and says ‘I hate it’

Williams, 44, returned to the testing pool before she could announce her comeback to professional tennis.

LONDON — Serena Williams took aim at tennis’ anti-doping system on Sunday ahead of her Wimbledon return, calling the system “unprofessional” and “unreasonable.”

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The 44-year-old Williams returned to the testing pool before she could announce her comeback to professional tennis and was asked Sunday about her experiences complying with the rules.

“It’s grueling. They changed the rules now. I didn’t know some of the rules. So apparently if you miss a test outside of your window, it still counts as missed. I’m like, I guess I can’t go pick up my kids,” said the seven-time Wimbledon champion, a mother of two. “It’s unprofessional. I hate it. I think it’s necessary, but I think a lot of the stuff, if I want to go places outside of my window, I should be able to go without having it count as a missed test.”