Former Wimbledon champion and World No. 6 Markéta Vondroušová has been suspended from professional tennis for four years for refusing an anti-doping test in December 2025, the international Tennis Integrity Agency (ITIA) announced Monday.

The 26-year-old Czech 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 Dec. 3, 2025, the ITIA, which oversees anti-doping in tennis, said.

Under anti-doping rules, the starting point for a sanction when a player refuses a test must be the same as if they had tested positive. 

During a hearing, Vondroušová explained that stress and poor mental health had affected her decision making, in addition to concerns for her safety.

In a Monday Instagram post, Vondroušová said she has never doped and never had a positive test.

“Just three days after the incident that ultimately changed my life, I was tested again,” she wrote. “The result was negative, just like every test before it.

“The past seven months have been the hardest of my life… I cooperated. I answered every question. I provided everything that was asked of me. I testified before the tribunal and did my best to explain what happened.”

In April, Vondroušová shared in an Instagram post that a “recent doping control incident happened because I reached my breaking point after months of physical and mental stress.”

Vondroušová said at the time that experts had confirmed that she suffered an Acute Stress Reaction and Generalized Anxiety Disorder — and “fear clouded my judgement and I just couldn’t process the situation rationally.”

She added in April that “we don’t take strangers at our doors lightly” after fellow Czech player Petra Kvitová survived a knife attack inside her apartment in Prostejov, Czech Republic in December 2016.

Vondroušová said she doesn’t know what comes next in her Monday post reacting to the suspension.

“The last seven months have left marks that will not disappear overnight,” she wrote. “They took away my confidence, and the sense of security I once had and honestly I do not know how long it will take to find those things again.”

In a statement ITIA CEO Karen Moorhouse said, “We understand that the testing process is uncomfortable, and acknowledge that it is an additional burden for players whose jobs already come with a high level of pressure and scrutiny, but it is essential to protect fair competition.

“Safety and welfare of players and our testers is really important to us. Our testers are well-trained, professional, and the gender of our testing witness always matches the player. They carry ID at all times, and players are able to verify their identity in other ways if they are ever unsure.”

Vondroušová’s suspension, which was determined an independent tribunal, will end on June 21, 2030.

While suspended, the 2023 Wimbledon champ is not allowed to play in, coach at, or attend any events organised or sanctioned by the ITF, WTA, ATP, the Grand Slams, or any national association.