World doubles No.1 Robert Farah has admitted testing positive for a banned substance, hours after he pulled out of the Australian Open for personal reasons.
The 32-year-old Colombian said the International Tennis Federation (ITF) informed him that he'd tested positive for Boldenona - an anabolic steroid - which he believes was the result of eating meat in his home country.
"I will not be able to play at the Australian Open, an event for which I had been preparing since December," Farah wrote on Twitter.
"A few hours ago, the ITF informed me of the presence of Boldenona in a test that I did on October 17, 2019 in Cali.
"Two weeks before the test mentioned... I did an anti-doping test in Shanghai, which had a negative result.
"And I was also tested at least 15 other times randomly in the international circuit throughout the year, with the same negative result.
"As stated by the Colombian Olympic Committee in 2018, this substance is found frequently in Colombian meat and may affect athletes' test results."
Farah, who won both the Wimbledon and US Open doubles titles in 2019, said he would consult his group of advisors and consider the next steps to prove he did not deliberately consume the banned substance.
"I am calm and confident in the results of this process, since I have always acted correctly and honestly in my life," he added. "I will work harder than ever to return to the courts in the shortest time possible."
Canada-born Farah teamed with long-time partner and fellow Colombian Juan Sebastian Cabal to win the ATP's doubles team of the year in 2019, but had already pulled out of this week's Adelaide International warm-up event.
A Tennis Australia spokeswoman told Reuters that Cabal, 33, was expected to remain in Melbourne and play in the doubles with another partner.
The Australian Open starts on Monday.