World No. 53 Viktor Troicki has been hit with an 18-month ban by the International Tennis Federation for violating tennis' anti-doping program, the ITF announced today.

Troicki will be suspended until January 24, 2015.

The 27-year-old Serbian failed to provide a blood sample when notified on April 15 that he had been selected to provide a urine sample and a blood sample at the Rolex Monte Carlo Masters event. Troicki provided a urine sample, but did not provide a blood sample.

The former world No. 12 said he was told it would be acceptable not to provide a sample on account of him feeling unwell that day, however the tribunal determined that Troicki's "actions constituted a failure and a refusal to provide a blood sample, and that his explanation for not doing so did not constitute compelling justification under Article 2.3."

In addition to the 18-month ban, Troicki forfeits ranking points and prize money from the Monte Carlo Rolex Masters. The Belgrade native lost to Jarkko Nieminen, 6-1, 6-2, in the Monte Carlo first round.

Troicki swept world No. 11 Marin Cilic to reach the round of 16 at Roland Garros before losing to No. 8 Jo-Wilfried Tsonga.

The former world No. 12 is one of the highest-profile players to be suspended for doping violation. In 2010, Troicki beat Michael Llodra to clinch Serbia's first Davis Cup championship.

At a press conference in Umag, Troicki called the suspension the "toughest moment of my career and of my life."

''I am innocent,'' Troicki said. ''I have never ever taken any prohibited substance or ever thought of doing so. I did not lie and this really hurts.''

In an official statement, Troicki explained his version as to what occurred in Monte Carlo:

“I was feeling awfully bad on April 15th before, during and after the 1st round match against Jarkko Nieminen. I was selected for urine and blood test after the match and went to the doping control station after showering and stretching. I gave the urine samples and told the doctor I was feeling really bad and I believed that drawing blood would make me feel even worse. I always feel awful when I need to draw blood and that day I was scared I would end up in hospital.

The doctor in charge of the testing told me that I looked very pale and ill, and that I could skip the test if I wrote an explanation letter to ITF about it. She dictated the letter to me and let me go without giving blood. She was very helpful and understanding…. Now I am being charged for refusing to undergo a blood test without justification. This is a real nightmare.  I was 100 percent sure everything was okay, just like my coach Jack Reader who was in the doping control station room with me during at least half of the procedure.”

Troicki added that he did have a blood test from the same doping control officer the next morning and that both his urine and blood test results came back “negative, totally clean.”

However the reason doping control rules state players must take blood tests immediately when requested is because certain prohibited substances can be washed out the body.

The ITF announcement is here:

Decision in the case of Viktor Troicki

The International Tennis Federation announced today that Viktor Troicki has been found to have committed an Anti-Doping Rule Violation under Article 2.3 of the Tennis Anti-Doping Programme (refusing or failing without compelling justification to submit to sample collection).

Mr. Troicki, a 27-year-old player from Serbia, was notified on 15 April 2013 that he had been selected to provide a urine sample and a blood sample in association with his participation at the Rolex Monte Carlo Masters event.

Mr. Troicki provided a urine sample, but did not provide a blood sample. He asserted to an independent tribunal that he was assured by the Doping Control Officer (DCO) that it would be acceptable not to provide a sample on account of him feeling unwell that day. However, the tribunal concluded that the DCO told Mr Troicki that she could not advise him as to whether his reason for not providing a blood sample was valid, and that no such assurances were given by her.

Accordingly, the tribunal determined that Mr. Troicki’s actions constituted a failure and a refusal to provide a blood sample, and that his explanation for not doing so did not constitute compelling justification under Article 2.3. However, the tribunal accepted that the stress that Mr. Troicki was under at the time entitled him to mitigation under Article 10.5.2.

Mr. Troicki’s commission of an Anti-Doping Rule Violation under Article 2.3 of the Programme was, therefore, confirmed, and the tribunal determined that he is suspended from participation for a period of 18 months, and so ending at midnight on 24 January 2015. It was also determined that Mr. Troicki’s results at the 2013 Monte Carlo Rolex Masters event should be disqualified, with resulting forfeiture of the ranking points and prize money that he won at that event.