Former World No.1 Simona Halep has been cleared to return to tennis with immediate effect after her four-year ban was reduced to nine months on Tuesday as a result of her recent appeal to the Court for Arbitration for Sport. 

Halep, a two-time Grand Slam champion, was provisionally suspended from competition on Oct. 7, 2022, after it was announced that she tested positive for the banned substance roxadustat at the 2022 US Open -- which she subsequently vehemently denied ingesting intentionally and attributed to a contaminated nutritional supplement. The Romanian was later charged with an additional anti-doping rule violation due to irregular findings in her Athlete Biological Passport, which establishes an individual profile of an athlete’s blood from regular blood tests.

Halep, now 32, was found to have committed anti-doping rule violations by an Independent Tribunal, and handed a four-year ban on Sept. 22, 2023. But she filed an appeal to the CAS -- the independent, highest tribunal for global sport -- and participated in a hearing in Lausanne, Switzerland last month. That body set aside the Independent Tribunal’s decision and partially upheld Halep’s appeal ruling that she bore "no significant fault or negligence" for her initial positive test, and she had established "on the balance of probabilities" that the supplement was contaminated. On the passport charge, the CAS also ruled that it was "not comfortably satisfied" that a violation of the appropriate statute of the Tennis-Anti Doping Program (TADP) had occurred and dismissed the charge. 

“Having carefully considered all the evidence put before it, the CAS Panel determined that Ms. Halep had established, on the balance of probabilities, that the Roxadustat entered her body through the consumption of a contaminated supplement which she had used in the days shortly before 29 August 2022 and that the Roxadustat, as detected in her sample, came from that contaminated product," the CAS statement read.

"As a result, the CAS Panel determined that Ms. Halep had also established, on the balance of probabilities, that her anti-doping rule violations were not intentional.

“Although the CAS Panel found that Ms. Halep did bear some level of fault or negligence for her violations, as she did not exercise sufficient care when using the Keto MCT supplement, it concluded that she bore no significant fault or negligence.”

The WTA has commented: "The WTA respects the processes that are in place to protect the integrity of the sport and provide a clean and fair sporting environment. With this, the WTA fully supports the decision by the Court of Arbitration for Sport (CAS) and we welcome Simona’s immediate return to play."

Halep has not competed since her first-round loss at the 2022 US Open.