For Australian Open champion Madison Keys, they were enough for her to break down in tears.
Former world No. 5 Andrey Rublev says they “can drive you crazy”.
World No. 1 Aryna Sabalenka calls them “really scary”; two-time Wimbledon finalist Ons Jabeur says she’s been “traumatised” by them.
“You’re freaking out,” Jessica Pegula, last year’s U.S. Open runner-up, told reporters in February. “I know there are a lot of girls who don’t sleep. Just lying in bed, making sure the doorbell works, every single phone is on — it can be very stressful.”
All of these players are describing the anti-doping protocols in tennis, which are based on the World Anti-Doping Agency (WADA) code. Nothing about them has changed, but since the back half of 2024, when two of the sport’s highest-profile players were sanctioned for breaching them, the anxiety players feel has intensified.
Five-time Grand Slam champion Iga Świątek was banned for one month after testing positive for trimetazidine (TMZ), a drug which enhances blood flow. The International Tennis Integrity Agency (ITIA) ruled that the breach was not intentional, accepting her explanation and evidence that she had taken a contaminated dose of melatonin.
Three months earlier, the ITIA announced that Jannik Sinner had twice tested positive for trace amounts of clostebol, a banned anabolic steroid. An independent tribunal convened by the ITIA accepted his explanation that the clostebol ended up in his system after his physiotherapist used a first-aid cream containing clostebol on a cut finger, and then gave Sinner massages through which he contaminated the player. WADA then appealed the tribunal’s verdict of “no fault or negligence.” After seeking a period of ineligibility of between one and two years, it reached a case resolution agreement with Sinner’s legal team in February, which saw the Italian receive a three-month ban.
The ITIA and WADA agreed that neither Świątek nor Sinner intentionally doped. But these cases have added to players’ fears about contamination, and the possible, severe punishment that can follow. They have also exacerbated fears about bans for missed doping tests, even if accidental: whereabouts rules dictate a starting ban of two years for three missed tests.
Jabeur called the Sinner and Świątek bans “a wake-up call.” At a London conference in May hosted by Sports Resolutions, which organizes the independent tribunals that rule on investigations, ITIA senior director Nicole Sapstead spoke of “a big uptake of players asking questions about contamination.”
With Sinner back on court at the Italian Open in Rome, this is what grappling with those fears looks like in practice, whether the rules should or will change and the particular challenges for tennis stars, who are independent players in an individual sport.
These fears are not unique to tennis. According to a U.S. Anti-Doping Agency (USADA) survey in 2022, 88 percent of 994 athletes from 76 sports reported anxiety around the risk of contamination from supplements and 86 percent of those athletes highlighted anxiety around whereabouts rules.
At the conference, Travis Tygart, the USADA chief executive, gave an evocative hypothetical example of an athlete staying overnight at their partner’s house for dinner and breakfast. In that time, he said, they would face 21 potential cases of contamination — from the food they might eat, to contact with a third party, to taking a glass from the dishwasher. That’s before considering whereabouts rules, which require an athlete to designate a set hour and location for possible testing every day.
Miss three of those windows within 12 months and they are deemed to have committed a doping violation, as the American Jenson Brooksby found out in 2023. Brooksby was initially banned for 18 months, later reduced to 13 on appeal. He has since returned to tennis, winning his first ATP Tour title at the U.S. Men’s Clay Court Championships in April.
In elite team sports, a dedicated person will organize what supplements players can take and who fills out their whereabouts. Teams often designate all players as being at the same location, like a training ground or team hotel, to keep things simple.
Tennis players are constantly moving around and traveling with few people, often deciding where to go at the very last minute. The more successful players will have team members to support them, but that’s not the case for everyone.
The players required to provide whereabouts information make up the International Registered Testing Pool (IRTP). It changes regularly, because it encompasses players inside the ATP and WTA top 100 for singles, as well as the top 10s in doubles and quad wheelchair tennis. If a player has a breakout tournament and shoots up the rankings, they can end up thrust into a system with which they are unfamiliar.
“Once you get the hang of it, it’s OK, but it’s confusing at first,” Pegula told reporters in Madrid in April.
“When you first start doing something new that’s so serious, you have a lot of anxiety. I know there are a lot of girls who were on their second or third strike and were like: ‘It was the worst year of my life.’”
The two highest-profile anti-doping cases in tennis in recent times have resulted from contamination. (Michele Limina / AFP via Getty Images)
Talking to a few reporters in Madrid, Keys recalled “immediately sobbing” when she realized that she had forgotten to update her whereabouts after changing her plans to try to qualify for the WTA Tour Finals nine years ago. Rather than being in Beijing where the testers showed up, Keys woke up in Linz, Austria, to the news that she had a strike against her name. “It’s so stressful,” she said.
Other players, including Jabeur and Denis Shapovalov, describe the app through which they submit their whereabouts crashing and being “traumatised by the bell of my house,” in Jabeur’s case, because she set her time as 5 a.m. This is a common strategy because it prevents testing from interfering with training patterns, but it also means disruption and setting a lot of alarms. Some described the stress of looking for internet connectivity to update whereabouts, while others, including Damir Džumhur, a Bosnian player ranked as high as No. 23 who got to his third strike, described that period as the most stressful of his life.
“For two months, I would have four alarms in the evening, making sure I didn’t forget to change if I’m going somewhere. And then in the morning, another four alarms,” he said. Even going to the bathroom at night can be a stressful balancing act, in case of not being able to urinate if testers come that morning.
In team sports, an athlete on their second or third whereabouts strike can often access additional support. Some major Olympic sports associations in Britain give those athletes a designated person to supervise their whereabouts requirements.
WADA spokesperson James Fitzgerald said via email last week that the whereabouts app had recently been redesigned in collaboration with athletes, “to make it more accurate, intuitive and reliable.”
Bianca Andreescu, who recently picked up a strike when she forgot to update her whereabouts while on a trip to Thailand, remembers struggling to get to grips with the system when she burst onto the scene in 2019 and accidentally ignored testers at her home. Fresh from winning the U.S. Open, she recalls “a knocking at like 5 a.m.”
She added: “But we had no idea who the heck it was. We’re like: ‘Oh my god, it’s some crazy fans. We’re not opening the door.’”
At the Madrid Open, men’s world No. 2 Alexander Zverev was visibly upset as he recounted a story of going to pick up his daughter from Nice airport in December and receiving a call telling him he had to get back home to Monte Carlo for a doping test. Zverev had given his window for that day in the morning and so was put out by being told that the test was compulsory.
“That is more annoying, because they’re taking the freedom of life away a little bit,” Zverev told reporters in April. “OK, if you want to come within the hour, that’s fine, because that’s the rule.
“If I pick my daughter up from the airport, that is more important. That system and that anti-doping system cannot decide for you that you have to leave everything and all of a sudden come back straight away. That’s wrong. That system can be better.”
Fitzgerald said that WADA was not involved in this incident, so could not comment, but that in general, “The point of out-of-competition testing is that it is a surprise. Sample collection can take place outside the times given (within certain parameters that respect reasonable access and privacy concerns).” Karen Moorhouse, the ITIA’s chief executive, echoed this view during an interview in May, though she said a player would be within their rights to decline an ITIA test outside of their designated window.
Zverev’s would-be test was conducted by the German National Anti-Doping Agency (NADA). Dr. Eva Bunthoff, the head of its testing department, said via email last week: “Doping controls will not only take place during the one-hour slot that athletes in the highest testing pool have to submit. The anti-doping regulations require doping controls at all times. According to the WADA Code, NADA Germany organizes doping controls outside of the so-called one-hour slot.”
In the end, the testers met Zverev, so he didn’t have to rush home. “I mean, we’re home, what, five weeks a year, maximum? On those five weeks, if we’re going out for one night, if you’re with your friends, if you want to spend some time away, if you even want to have a nice romantic dinner with your wife or girlfriend or whatever, they can destroy that within a second,” Zverev said.
“So, if you want to come at the right time, that’s fine. But if you want to just completely mess with our lives, then that’s not fine.”
The whereabouts rules are in place to ensure a fair and consistent method of testing for all athletes — not just ones who come from nations with conscientious anti-doping practices. But it’s contamination, which is at the center of the Sinner and Świątek cases, that is accelerating the feeling of paranoia across both tours in recent months.
Jannik Sinner has returned to competitive tennis after an 85-day anti-doping ban. (Marco Bertorello / AFP via Getty Images)
The sensitivity comes partly from the crackdown on potential micro-dosing of banned substances across sports, with increasingly sophisticated testing labs detecting lower and lower concentrations of banned substances to ensure that any genuine cheats cannot get around being tested. For tennis players, this has engendered even more fear about what they should and should not consume.
Świątek ended up with a one-month ban despite taking a melatonin pill recommended by her doctor as safe. It was only by laboratory-testing an unopened batch from the same production run that she could prove the contamination — the kind of defense players with lesser resources would struggle to provide. In Sinner’s case, the clostebol came from a first-aid cream readily available in Italy called Trofodermin, whose box has a warning about its anti-doping status printed on it.
Players have described heightened anxiety about the medicines they take, as well as what they eat and drink. During a news conference at January’s Australian Open, 2021 U.S. Open champion Emma Raducanu said that she left an insect bite untreated for fear of a banned substance entering her body. At May’s Italian Open in Rome, she reiterated her concerns.
“Even if it’s not prohibited on the anti-doping list, you don’t know if it’s contaminated by another product. It can show a green tick, but if it’s contaminated you will still get screwed over,” Raducanu said. She also described fears of deliberate contamination at restaurants or bars.
“It’s really hard, especially if you are noticeable and the waiter recognises you. It’s something I do worry about,” she said.
Rublev expressed similar sentiments ahead of the Madrid Open in April. “I’ve become wary of taking medication,” he told reporters.
“If I feel sick, I avoid taking anything. In my case, I’m lucky to be able to talk to doctors, but that’s not the case for everyone. The doubts even extend to food; there are prohibited substances even in meat. It can drive you crazy.”
At the same event, Shapovalov, the Canadian world No. 28, said that he cancelled a prescription after research found a small risk of the medicine breaching anti-doping protocols. The measures players take vary according to their concerns — and their means.
Casper Ruud, who won the Madrid Open, said he doesn’t “dare to buy anything locally because it’s just such a big risk” at a media huddle in the Spanish capital. He carries his supplements and medications to every event.
At the same event, Jabeur told reporters: “I go the old-fashioned way and have honey. Because sometimes I’m going through the list and I can take it. But sometimes even when it’s not prohibited, you’re like: ‘Is it really not prohibited? I don’t even know, I’m not 100 per cent sure.’”
All the players interviewed for this story said that they understand why rules need to be so stringent, but that it doesn’t make the measures they have to take any less exhausting. Pegula hides her supplements and anything she might consume when staying in hotels, for fear of tampering.
“It’s paranoid, but if someone comes into the room, there’s no real defence for that,” she told a few reporters in Madrid.
“It’s part of the job, but that doesn’t mean that it’s enjoyable to freak out about every drink you’re touching and whether you updated your hour every single day for the rest of your life. It wears you down so when I retire, I’m looking forward to not having to deal with that.”
Leading WTA players Sabalenka, Jasmine Paolini and Mirra Andreeva said they wouldn’t risk drinking from a water bottle if it had left their sight. Andreeva also explained that she frequently has to tell her dad not to drink from her bottle due to the contamination risk.
At the Sports Resolutions conference, Tygart described the universe in which athletes exist to avoid contamination as “pretty ridiculous.”
“Everybody is afraid,” Paolini said in Madrid.
In December 2025, WADA will confirm or reject proposed changes to its code, on which the tennis anti-doping regulations are based. One of the proposed changes covers contamination.
Only anti-doping rule violations linked to a contaminated substance not on its prohibited list are eligible for a reduced punishment. This is what happened in Świątek’s case: her melatonin, which is not on the prohibited list, was contaminated with TMZ, which is. In Sinner’s case, the substance with which he was contaminated was banned at first principle. This is why WADA originally sought a one- to two-year ban. It switched gears and settled for 85 days after determining that it “would have been very harsh” for Sinner to receive a longer ban, spokesperson Fitzgerald said in a statement in February.
Under the proposed reforms, the language in the code would change from “contaminated product” to “source of contamination.” The “unforeseeable” presence of a banned substance in an athlete’s body, whether from food or exposure via a third party, would be grounds for just a reprimand or a shorter, proportional ban if successfully proven.
Iga Świątek has said that the stress of proving her innocence heavily affected her mentally. (Marco Bertorello / AFP via Getty Images)
“We’re racking up positives that have nothing to do with intentional cheating,” said Tygart in a phone interview in May.
“It’s hard for people who understand the system and those who live within it to comprehend why we continue to have rules that are behind the science that don’t stop doping, but knowingly punish innocent people.”
Tygart also spoke of the “incredibly onerous obligations” anti-doping rules place on athletes, adding that there is “definitely” more anxiety for someone in an individual sport than a team one.
Fitzgerald said: “Anyone who claims there is a straightforward solution to this issue is not being honest. This is a complex and nuanced area of anti-doping in which WADA always strives to strike the right balance for the good of athletes and clean sport.”
Moorhouse, who worked in rugby league for over a decade before joining the ITIA, said: “Recent cases have made people think about this in a way that they hadn’t previously. This is a good thing in terms of having those conversations and players realising how you can breach the rules unintentionally and how the responsibility sits with them and that strict liability.
“Where we want to get to is having players who understand the rules, take them seriously, take the right steps, but we don’t want these players going to extremes.”
“The challenge for anti-doping organisations is traversing that line between somebody saying it was innocent versus somebody who has taken something without making any checks about what they’re taking,” Sapstead said.
“I’m still floored when you read decisions around the anti-doping community about products where the name is probably quite a big giveaway about a product containing something.”
A big part of this is education, which the tours and the ITIA offer to the players from a young age. Several players made accusations of “preferential treatment” after the news of Sinner and Świątek’s short bans, even though their cases followed ITIA protocols.
At the Sports Resolutions conference, former rower Emily Cameron-Blake described feeling “absolutely petrified every day that you’re going to come into contact with something or miss a whereabouts call.” Tennis players can identify with that feeling, especially in recent months. Świątek herself said during a news conference in Madrid: “You think about this all the time… there’s a lot of pressure with that, and it’s not easy to manage.”
It only gets harder further down the tennis ladder.
(Photos: Hannah Peters, Clive Brunskill / Getty Images; Illustration: Demetrius Robinson / The Athletic)