Former Wimbledon champion Marketa Vondrousova has been suspended for four years after refusing an anti-doping test, the International Tennis Integrity Agency (ITIA) announced on Monday. The ban follows an out-of-competition test attempt at her home in December 2025 and was imposed after an independent tribunal reached its decision following a hearing held this month.
The Czech player, 26, cited “mental stress” and fear in explaining her reaction, saying the testing agent “rang my door late at night without properly identifying themselves.” The tribunal, however, concluded the evidence offered “no compelling justification” for the refusal, according to the ITIA.
The case is significant because refusal to submit to testing is treated seriously under anti-doping rules, and the ITIA stressed that the system cannot allow athletes to be better off by refusing a test than by taking one.
What the ITIA said happened on December 3, 2025
The ITIA said Vondrousova “did not submit a sample when notified by a Doping Control Officer (DCO) during an out-of-competition test attempt at her home at around 8 p.m. on 3 December 2025” and that she signed a refusal form instead.
The agency also outlined the broader framework that governs such tests. Tennis players and other professional athletes are required to specify where they will be available for a one-hour period each day to provide samples for testing. In this case, the female testing agent arrived outside the assigned hour Vondrousova had signed up for that day, as part of a surprise test.
Under the rules described in the report, athletes are required to submit for testing if they are located for a surprise test outside their assigned hour. The ITIA noted that if an athlete is not found when a tester shows up outside assigned hours, there is no sanction. Here, the issue was not that Vondrousova could not be located, but that she refused to provide a sample after being notified.
Vondrousova presented explanations to the tribunal that stress and poor mental health affected her decision making, along with concerns for her safety because she claimed the tester did not identify herself. The tribunal considered those explanations as well as testimony from the doping control officer who attempted to conduct the test, and ultimately rejected the justification.
ITIA CEO Karen Moorhouse said the length of the sanction reflects the structure of the rules around refusals. “We recognize this is a significant ban,” Moorhouse said. “And the reason for that, stepping back, is that you can’t have an anti-doping system where a player is in a better place by refusing to take a test than they would by taking a test and testing positive. So that feeds into the structure of the doping rules that provides for a starting point in the four-year ban for refusing to take a test.”
Moorhouse also emphasized the role of surprise testing. “Unpredictable testing is an essential tool to protect clean sport,” she said, adding that the tribunal supported that principle and that the case is “an important reminder that players can be tested at any time, in any place, and that refusal comes with significant risk.”
Vondrousova’s public explanation
Vondrousova discussed the incident in an Instagram post in April, describing the impact on her mental health. “It is very tough for me to talk about this, but I want to be transparent with you about my mental health,” she said. “The recent doping control incident happened because I reached a breaking point after months of physical and mental stress.”
She was represented by Los Angeles-based lawyer Howard Jacobs, described in the report as a specialist in doping rules cases.
Ban length, appeal option, and wider context
According to the ITIA, Vondrousova’s ban expires on June 21, 2030, and she can appeal the decision to the Switzerland-based Court of Arbitration for Sport.
The report also placed the case in the context of other recent high-profile tennis anti-doping matters, naming Simona Halep, Jannik Sinner and Iga Swiatek. It noted that Sinner accepted a three-month ban in a settlement with the World Anti-Doping Agency at the start of last year, while Swiatek accepted a one-month suspension at the end of 2024. The report added that Halep, Sinner and Swiatek each proved they were not entirely responsible for their positive tests.
The ITIA said it would not disclose whether any inconsistencies were found in Vondrousova’s previous anti-doping history. Nicole Sapstead, the ITIA’s senior director of anti-doping, said: “We wouldn’t disclose that,” adding: “Obviously we look at all things like that.”
Vondrousova is a former Wimbledon champion, becoming the tournament’s first unseeded female champion when she beat Ons Jabeur in the 2023 title match. The report also noted she reached a career-high ranking of No. 6 in 2023 and was a French Open finalist in 2019, losing to Ash Barty. Wimbledon starts next week.
