Two-times major winner Simona Halep of Romania has been provisionally suspended after testing positive for the banned substance roxadustat, the International Tennis Integrity Agency (ITIA) said on Friday.
Halep, ranked ninth in the world, was tested during the US Open and both her A and B samples confirmed the presence of the drug.
"Simona Halep, a 31-year-old Romanian tennis player, has been provisionally suspended under Article 7.12.1 of the 2022 Tennis Anti-Doping Programme (TADP)," the body said in a statement.
"The sample was split into A and B samples and the subsequent analysis found that the A sample contained FG-4592 (Roxadustat), which is a prohibited substance listed in the 2022 World Anti-Doping Agency (WADA) Prohibited List."
Halep described the ban as the "biggest shock of her life".
"Throughout my whole career, the idea of cheating never even crossed my mind once, as it is totally against all the values I have been educated with. Facing such an unfair situation, I feel completely confused and betrayed," she wrote on Twitter.
'Ronaldo refused to come on as sub against Spurs'
Niemann files $100m defamation lawsuit against Carlsen
PIX: Barcelona ease past Villarreal; Arsenal sink PSV
Ronaldo off the squad in EPL match against Chelsea
Shami is Moody's pick to lead attack against Pakistan