Last year, tennis authorities revealed that former Australian player Marinko Matosevic was under the International Tennis Integrity Agency (ITIA) investigation for a ‘Prohibited Method,’ an inquiry he says he never knew existed. Retired since November 2018 after last competing in February, the 40-year-old now fires back, branding the ITIA corrupt as the controversy resurfaces.

Reaching out to The First Serve, former Australian player Marinko Matosevic made a public confession about his ongoing ITIA case:

“It’s with a heavy heart and a clear mind as I write this. I have been under investigation by the ITIA since the Rome masters 2024. The investigation is centred on a Prohibited Method I used in February 2018. I can confirm it’s true.”

Back on August 6, 2025, host Brett Phillips on The First Serve Live on SEN revealed the following: “It is the First Serve’s understanding that the coach of Jordan Thompson, former Australian player Marinko Matosevic, is under investigation by the International Tennis Integrity Agency.

“In their words, we publish details of all completed cases when they are concluded. Until that point, we do not comment on speculation, individuals, or whether someone is under investigation or not. The First Serve has spoken to Jordan Thompson himself to alert him to the information, also asking him separately about rumors of a split between the pair post Wimbledon, which is news to him in terms of the coaching split, and that he has no knowledge of any investigation going on.”

Now, on February 2, 2026, Matosevic explained why he chose to admit wrongdoing despite disputing the process itself. He claimed the case against him was deeply flawed and unfairly constructed.

“Even though the ITIA has no real evidence of my wrongdoing, I have decided to admit what I did due to the corrupt process and the ridiculous nature of the other charges.”

The former world No. 39 went on to reveal the circumstances behind the violation. He described a difficult personal period that led to a decision he now deeply regrets.

“Under desperate circumstances (I had some health issues in 2017), I stupidly and recklessly did a blood transfusion in Morelos, Mexico. I was so disgusted with myself, I retired the following week at the age of 32 and a half. Shortly after, I realized how precious life is and how serious and reckless my decision was. I wasn’t involved in tennis at all for almost 2 years and pro tennis for 3.”

Matosevic said his intention now is to warn younger athletes. He urged them not to compromise their health or future for short-term decisions. While doing so, he launched a scathing attack on the ITIA and its investigative methods. He accused the agency of intimidation and misuse of authority:

“I am writing this letter to let the tennis world know how corrupt and unjust the ITIA process is. They take your phone under threatening circumstances and make legal cases over photos and text message assumptions that are literally over 5 years old. The whole process is corrupt and lacks credibility, as we have seen over the last few years! These are man-made rules that get changed on a whim and to suit questionable objectives; they are not moral or right!”

Matosevic also dismissed additional accusations leveled against him. He said those charges were built on weak interpretations of old messages.

“The other ‘complicity’ charges they have against me are total nonsense and have been put together with nothing but text messages from years ago, using more made-up laws like ‘intent’”

After consulting several knowledgeable individuals, Matosevic said he reached a stark conclusion. He believes tennis governance needs structural reform.

“The players have all the power; if they come together, they can achieve real positive change! Due to the reasons mentioned above, I will not be attending the scheduled hearing next week and stop the process myself and will cease all communication with the ITIA. The truth will set you free!”

Matosevic last played professionally in February 2018. He stopped after losing in the Indian Wells Challenger qualifying final. His retirement was officially announced later that November.

He never won an ATP title but enjoyed success on lower tours. He claimed four Challenger titles and five Futures titles during his career.

At his peak in 2013, Matosevic reached world No. 39. He also represented Australia in the Davis Cup and was briefly the nation’s highest-ranked player.

In 2025, other cases followed similar paths. Former world No. 40 Max Purcell accepted an 18-month suspension. Tom Fancutt was provisionally suspended. Both admitted to using a “prohibited method” under ITIA rules.

With Matosevic now speaking out forcefully, criticism of the ITIA continues to grow. Several former players in recent years have also openly questioned the agency’s credibility and conduct.

Simona Halep criticizes ITIA’s double standards following Iga Swiatek’s one-month ban

Along with Marinko Matosevic, former world No. 1 Simona Halep has also questioned the credibility of the ITIA. She raised her concerns two years ago during Iga Swiatek’s doping controversy.

In 2024, Iga Swiatek, the current world No. 2, tested positive for the heart medication trimetazidine (TMZ). The result came from an out-of-competition sample and quickly drew global attention.

Halep’s case unfolded earlier. She returned to professional tennis in March 2024 after serving a provisional suspension that began in October 2022. She had tested positive for roxadustat at the US Open.

The Romanian star believes the ITIA lacks consistency in how it handles doping cases. She has openly questioned why similar cases have led to vastly different outcomes.

“I have always believed in good, I have believed in the fairness of this sport, I have believed in kindness,” Halep wrote on Instagram. “The injustice that was done to me was painful, is painful and maybe will always be painful.”

She continued by directly challenging the ITIA’s decision-making: “How is it possible that in identical cases that happened at about the same time (of the season), ITIA has completely different approaches, to my detriment?”

She also asked, “Why is there such a big difference in treatment and judgment?” 

As Matosevic now raises similar concerns, the tennis world will closely watch how the ITIA responds in the coming days.