She’s no dope.

Tennis star Serena Williams, fresh off an impressive run at Wimbledon, griped this week about her latest drug test — alleging “discrimination” over her frequent testing.

“…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,” she tweeted Tuesday night. “But I’m ready to do whatever it takes to have a clean sport so bring it on. I’m excited.”

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The 23-time Grand Slam champ has been tested five times in 2018, according to the U.S. Anti-Doping Agency’s database — at more than twice the frequency of many other leading American women in tennis, as Deadspin pointed out last month, and more often than top American male players. For example, Sloane Stephens has been tested just once; Madison Keys has been tested twice; Williams’ sister, Venus Williams, has been tested twice; and CoCo Vandeweghe has been tested twice, per the database.

Deadspin reported in late June that a doping control officer had shown up to Williams’ Florida home on June 14 for an unannounced drug test. An assistant reportedly let the officer in while Williams wasn’t home; when the athlete returned, a “standoff” ensued and she refused to take the test, according to the report. If successful, that test would have been her sixth this year.

Williams later addressed the incident with reporters, claiming the officer had arrived 12 hours prior to her scheduled appointment — rendering the attempt a missed test. She added she’d been talking to USADA about the issue, and said she was “OK” with her frequency of testing this year, “as long as everyone is being treated equally.”

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“I despise having people in our sport that aren’t being honest,” she said, according to ESPN. “I’m totally OK with testing and I encourage it. What I want to know, if everyone is getting tested, that we are really working to keep this sport clean.

“Tennis has given me so much. … I feel like equality, that’s all I’ve been preaching; it’s all about equality. If that’s testing everyone five times, let’s do it. Let’s be a part of it. It’s just about being equal and not centering one person out. Just due to the numbers, it looks like I’m being pushed out. Just test everyone equally.”

A USADA rep declined to comment when reached by Moneyish. The Women’s Tennis Association did not immediately return a request for comment.

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“An important part of USADA’s testing program is the ability to test athletes without any advance notice in an out-of-competition setting,” reads a page on the USADA’s website. “Athletes are subject to testing 365 days a year and do not have ‘off-seasons’ or cutoff periods in which testing does not occur.”

Considerations like doping analysis stats, history of doping in the sport, and physical demands of the sport factor into the testing of athletes, according to the organization. “The term ‘random’ is not an accurate way to describe anti-doping testing in the United States, as USADA uses various factors to strategically plan when and where we test athletes in order to achieve maximum success in deterrence,” USADA says.