(July 25, 2013) -- Viktor Troicki was dealt a pretty harsh blow to his career on Thursday when the International Tennis Federation suspended the 27-year-old Serbian for 18 months due to a violation of the Anti-Doping Rule.

During April’s Rolex Monte Carlo Masters event this year, Troicki was asked to provide both a urine sample and blood sample for a random drug test. Although he submitted a urine sample, he refused to provide a blood sample, reportedly saying that he did not feel well that day.

The tribunal ruled that Troicki’s failed compliance violated the Anti-Doping Rule, and his explanation for not supplying the blood sample was not sufficient justification. With the immediate suspension, which ends at midnight on Jan. 24, 2015, Troicki must also forfeit all results, ranking points and prize money won at the 2013 Monte Carlo Rolex Masters tournament. He lost in the first round to Jarkko Nieminen, but earned 9,305 Euros (about $12,300).

Troicki is currently ranked No. 53 on the ATP Tour, and he reached the round of 16 at Roland Garros, followed by the third round at Wimbledon. His last tournament was at Bastad, Sweden, where he fell in the second round to No. 104 Thiemo de Bakker.