The International Tennis Integrity Agency (ITIA) confirmed on Thursday that Bartunkova, who reached a career-high world singles ranking of 226 in April 2024, provided samples that tested positive for TMZ while competing at an ITF W50 event in Trnava, Slovakia, in February and an ITF W75 event in Maribor, Slovenia, in March.

The 18-year-old reached the girl's singles final at Wimbledon last year, where she lost to American Clervie Ngounoue, and also played in the singles semi-finals and the doubles final at the 2022 Junior French Open. She has been provisionally suspended by the TADP, which considers TMZ a prohibited non-specified substance and lists it as a hormone and metabolic modulator that increases blood flow. The agency said the second test in Maribor confirmed the earlier results from Trnava and that Bartunkova did not have a valid TUE for the heart drug.

Findings for non-specified substances carry a mandatory provisional suspension, which in the case of the Czech player is effective from 16 April and prevents her from playing, coaching or participating in any tennis event authorised or sanctioned by any member of the ITIA (ATP, ITF, WTA, Tennis Australia, Fédération Française de Tennis, Wimbledon and USTA) or any national federation.

TMZ made global headlines on 20 April, when the New York Times and German broadcaster ARD reported that 23 Chinese swimmers had tested positive for the drug ahead of the Tokyo Olympics in 2021. The World Anti-Doping Agency (WADA) initially investigated the incident originally and allowed the athletes to compete after accepting China's findings that they had unknowingly taken the drug with food during a competition in late 2020 and early 2021. 

Many national agencies, federations and athlete-led pressure groups reacted with outrage to the revelations, pointing to Russian figure skater Kamila Valieva, who received a four-year ban after testing positive for the same substance in 2022, as a clear case of double standards. WADA has since sought to defuse the growing backlash over its handling of the scandal, announcing an independent investigation led by former Swiss prosecutor Eric Cottier.

But just last week, another TMZ case surfaced involving Olympic refugee team runner Anjelina Nadai Lohalith, who was also provisionally suspended after testing positive for the cardiac stimulant commonly used to prevent and treat the symptoms of angina. The Athletics Integrity Unit (AIU), like the ITIA in the case of Bartunkova, has provisionally suspended Lohalith pending a final decision. Regarding the tennis suspensions, the ITIA is an independent body established by its members to promote, encourage, enhance and safeguard the integrity of professional tennis worldwide.