Former Top-100 suspended after positive doping test, following decisive Billie Jean King Cup win for Croatia

The former Top-100 player Jana Fett was found guilty of a violation of anti-doping regulations after returning a positive result for the presence of three prohibited substances, a case that has resulted in her provisional suspension from the professional circuit and has kept her away from competition since late 2025.

The Croatian tennis player, currently ranked No. 189 in the world and 29 years old, was notified by the International Tennis Integrity Agency (ITIA), which confirmed this Friday the temporary sanction while the disciplinary process continues. As confirmed by the ITIA on Friday, the Croatian tested positive for “Ostarine, traces of LGD-4033, and GW501516.”

The anti-doping control that led to the case was carried out on November 16, 2025, during the Billie Jean King Cup playoffs held in Varazdin, Croatia. On that occasion, Fett teamed up with Petra Marcinko in doubles against Colombia, sealing the Europeans’ victory in the tie against the South Americans with a 6-4, 6-3 win over Camila Osorio and Yuliana Lizarazo. With this result, the Europeans secured qualification for the 2026 qualifying round.

According to details provided by the ITIA, the collected sample was divided into the usual A and B samples. Analysis of the A sample revealed the presence of Ostarine, a selective androgen receptor modulator (SARM), as well as two different metabolites associated with that substance. Subsequently, the B sample fully confirmed the initial findings, thereby validating the positive result.

Both Ostarine and its metabolites are included on the list of prohibited substances under the current anti-doping regulations, within the categories of anabolic agents and metabolic modulators.

Fett’s provisional suspension came into effect on December 22, 2025, which explains her complete absence at the start of the current season. From that point on, the player has not competed in any tournament nor appeared at official calendar events, fueling speculation until the public confirmation of the case.

According to the regulations, Jana Fett has the right to appeal the provisional suspension and to present her defense before the relevant bodies, although she has not exercised that option so far. While the sanction remains in force, the Croatian player is strictly prohibited from competing, training, or even attending tennis events organized or sanctioned by ITIA member entities, including the WTA, ITF, ATP, Grand Slam tournaments, and affiliated national federations.

The 29-year-old Croatian reached her best ranking as world No. 97 back in 2017, when she was just 20 years old. She came close to the top 100 again during the 2023–2025 seasons, played final rounds of Grand Slam qualifiers, reached the second round of Roland Garros 2024, and won several ITF titles.

Fett was at the Australian Open one year ago; in fact, she defeated Alexandra Eala in the qualifying rounds and was eliminated in the first round by Harriet Dart. She also competed at the Stuttgart Open during the clay swing, where she defeated Olympic silver medalist Donna Vekic, before later being beaten by six-time major champion Iga Swiatek in the second round.