Simona Halep said she will “fight for the truth” after the former World No 1 and Wimbledon champion was provisionally suspended from tennis for testing positive for a banned substance at this year’s US Open.

A statement from the International Tennis Integrity Agency said Halep failed a doping test after her sample contained the anti-anemia drug Roxadustat, which is a prohibited substance on the World Anti-Doping Agency’s list.

But in response, two-time grand slam champion Halep said the news had come as the “biggest shock of my life” and vowed to “fight until the end” to clear her name. Halep said she “never knowingly took any prohibited substance” and felt “confused and betrayed” by the findings.

Roxadustat is a drug that increases oxygen-carrying capacity and is in the same category as EPO, another blood-boosting drug, on Wada’s list of prohibited substances.

Halep’s failed drugs test is the most significant to hit tennis since former World No 1 Maria Sharapova was banned for 15 months for testing positive for the banned substance meldonium in 2016.

Halep, who won the French Open in 2018 and Wimbledon the following year, said in a statement on social media: “Today begins the hardest match of my life: a fight for the truth.

“I have been notified that I have tested positive for a substance called Roxadustat in an extremely low quantity, which came as the biggest shock of my 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. I will fight until the end to prove that I never knowingly took any prohibited substance and I have faith that, sooner or later, the truth will come out.

The Romanian, 31, will be ineligible to compete in or attend any sanctioned tennis events organised by the governing bodies of the sport during her provisional suspension, the ITIA’s statement continued.

The ITIA said Halep had been informed of her positive test on October 7. The statement said Halep requested for her B-sample to be analysed, which the ITIA said confirmed the findings in the A-sample.

Halep was knocked out of the US Open following a shock loss to Daria Snigur in the first round and announced last month that she had brought her season to an end following nasal surgery.