The conversation around anti-doping procedures in professional tennis has intensified at Wimbledon 2026, with several leading players voicing concerns over how testing is conducted. Former US Open champion Coco Gauff revealed that an encounter with a doping control officer left her in tears, while other players, including Ajla Tomljanovic and Jessica Pegula, questioned whether the current system adequately balances athlete welfare with the need to protect the integrity of the sport.
The debate has gathered momentum following the four-year suspension handed to 2023 Wimbledon champion Marketa Vondrousova. The Czech player was not banned for testing positive for a prohibited substance but for refusing to provide a sample during an out-of-competition anti-doping test, a violation that carries penalties equivalent to a positive test under the World Anti-Doping Agency (WADA) Code.
Speaking after her opening-round victory at Wimbledon, seventh seed Coco Gauff described one of her previous interactions with an anti-doping tester as emotionally distressing. “I’m not going to lie, some of them can be pushy, make you feel like you’re doing something wrong,” Gauff said, “One time she came outside my time slot. But the way she was speaking to me on the phone, it literally made me cry afterwards,” the 22-year-old American said. “I found out I was in the right, and I didn’t have to do anything.”
Under the International Tennis Integrity Agency (ITIA) anti-doping programme, players competing on the professional tour must provide a daily 60-minute time slot during which they are guaranteed to be available for testing. However, the rules also state that if a doping control officer locates and officially notifies a player outside that designated window, the athlete is still required to complete the test.
The system, designed to ensure effective out-of-competition testing, has often been criticised by players who say the procedures can be confusing and stressful, particularly when travel schedules and changing accommodations are involved. Australian player Ajla Tomljanovic echoed those concerns ahead of her first-round match, admitting she fears making an administrative mistake that could have career-changing consequences.
“I’m very scared of the system because it feels broken,” she said. “I’ve had a few experiences of my own where it was about technicalities and when I speak to people in charge they’re not helpful – I don’t want to say they don’t care – but they weren’t very helpful at all to explain things or just show some sort of compassion when I was nowhere near missing a test or testing positive.”
Tomljanovic explained that she struggled while learning how to use the whereabouts application that players must regularly update.
“I was new to the whole system. And I was at two fails for a month and I knew if I get a third one accidentally I would be out for at least two, three years,” she said. “It’s in a way, I won’t say no fault of my own but it’s not to the degree of being banned and smearing your name. In that sense, I think there’s so much to improve on.”
The scrutiny intensified after Vondrousova received the maximum four-year suspension following an independent tribunal hearing. According to the ITIA, the incident occurred in December 2025 when a doping control officer arrived at the Czech star’s apartment outside her nominated testing window. Vondrousova challenged the timing of the visit and declined to provide a sample. The tribunal later concluded that she had refused testing without sufficient justification, despite arguments regarding her emotional distress during the incident.
The ITIA subsequently released a detailed explanation of the case, reiterating that players who are located and officially notified by a doping control officer outside their nominated hour are still required to submit to testing. The agency also emphasised that under WADA regulations, refusing a test is treated as seriously as returning a positive result because athletes using banned substances could otherwise avoid detection simply by declining to be tested.
The decision has divided opinion across the tennis community.
Fourth seed Jessica Pegula admitted she sympathised with Vondrousova despite not knowing every detail of the case. “I feel, like, for Marketa. For something like that, for four years, you’re ruining someone’s career over something that could have really just been a complete misunderstanding, and I just don’t think that’s fair. I think the sentencing is so harsh,” Pegula said.
“I don’t quite understand the difference between that and then obviously what happened with (Jannik) Sinner and Iga (Swiatek),” she said. “They justified what the rules were and why it was the way it was.”
Pegula’s comments referenced two of tennis’ most widely discussed anti-doping cases in recent years. World No. 1 Jannik Sinner accepted a three-month suspension in early 2025 after WADA appealed an earlier ITIA ruling that had accepted his explanation of accidental contamination involving a banned anabolic steroid. Meanwhile, defending Wimbledon women’s champion Iga Swiatek served a one-month suspension in 2024 after testing positive for trimetazidine, with investigators concluding the substance entered her system through contaminated melatonin medication used to treat jet lag.
Former Wimbledon champion Serena Williams also acknowledged the mental burden associated with the anti-doping programme, describing the testing process as “grueling.”
The ITIA has defended its procedures, noting that it carried out more than 8,000 anti-doping tests across professional tennis during the previous season while receiving only a small number of complaints. The organisation said athlete feedback is welcomed and confirmed that tennis follows the global anti-doping framework established by WADA.
The agency also pointed out that the World Anti-Doping Code is scheduled for review in 2027, with athletes from multiple sports expected to participate in consultations regarding potential changes.
“We understand the system can seem challenging,” the ITIA said, “but it is there to protect players, not to trip them up. If players are ever unsure about a test, have questions, or would like to provide feedback on their experience, we want to hear about it.”
As Wimbledon progresses, the discussion surrounding anti-doping protocols has become almost as prominent as the on-court action. While players continue to support rigorous testing to preserve fair competition, many are calling for a system that is clearer, more transparent and more compassionate without compromising the fight against doping.
