Darren Cahill, Simona Halep's former coach has come to the defence of the Romanian following her provisional suspension from tennis for failing a drugs test. 

In what is tennis' biggest drugs controversy since the Maria Sharapova saga, the world No 9's sample was found to have contained the blood-booster Roxadustat. She denied wrongdoing in a post on social media. 

Cahill has said Halep's 'integrity is faultless' and that there is 'no chance' she would have purposely or knowingly taken the banned substance. 

In a lengthy statement posted on Instagram, the 57-year-old wrote: 'Even though I’m no longer working with Simona, I’d like to speak clearly to the person I know and the athlete that I worked with for 6 years.

'Firstly, and most importantly, there is NO chance Simona knowingly or purposely took any substance on the banned list. None. Zero.

'She is an athlete that stressed about anything prescribed to her by a medical professional (which was rarely), or about any supplement that she used or considered. Simona wore out the words “please double check this, triple check this to make sure it’s legal, safe and permitted. If you are not sure, I’m not taking it.”

'We both believe in the ITIA testing program and would often discuss the number of times she was tested, both at tournaments and randomly. She did it without complaint, with the reassurance of knowing other athletes were being tested just as frequently. Competing against clean athletes was important to her. It’s important to everyone and while the system is not perfect, it works.'

Cahill guided Halep to her first grand slam title at Roland Garros in 2018.

When the pair stopped working together in September 2021, Halep thanked Cahill  'for making me a better tennis player and a better person'. 

'Simona’s integrity is faultless, she respects her peers, she loves the game and she always has her feet firmly planted on the ground as a humble, approachable champion,' Cahill continued in the statement.

'I have sat proudly in awe of the person that she has matured into, watching the compassion she has shown others. I’m not talking about the stuff that the tennis world gets to see, I’m speaking about the kindness and care that very few are fortunate to experience. The kind of actions that are done for love and not for publicity.

'Honesty has always been her greatest strength and her biggest weakness. We would often laugh about the fact that she can’t act and can’t tell a little white lie. Ask her a question in a press conference and she will blurt out an honest answer. She wears her mood on her shoulder for the world to see, for good and for bad. That is Simo. What you see is what you get. She built an amazing career and legacy by doing things the hard way. The right way.

'Due process will now follow to reveal answers to many questions. As Simona said, the hardest match of her life starts now.

'I believe in her. I always have and can honestly say never more than right now on this particular issue.

'I stand with Simo.'

Roxadustat is banned by the World Anti-Doping Agency. The drug is used to help spare patients with kidney disease the pain of injections if they develop anaemia and helps stimulate the production of red blood cells.

Until recently, symptoms could be treated only with medicine that patients usually inject themselves, alongside iron infusions in hospital twice a year. But the new tablet, which is taken three times a week at home, has proved to be just as effective. 

It works by mimicking the body's natural response to reduced oxygen in the blood – blocking an enzyme that limits the production of new red blood cells while increasing the absorption of iron in the blood. 

Studies show the drug is just as effective at boosting oxygen levels and alleviating symptoms as the current treatments. 

Halep is one of the most recognisable names in women's tennis. She won the French Open in 2018 before lifting the Wimbledon title the following year, while she is also a former world number one.