Viktor Troicki has been handed an 18-month ban from tennis for a doping violation.
The world number 53 failed to provide a blood sample when requested during the Monte Carlo Masters back in April.
The 27-year-old claimed that he had asked to be excused from the blood test due to feeling unwell, but the International Tennis Federation have rejected his claim.
An ITF statement read: "Viktor Troicki has been found to have committed an Anti-Doping Rule Violation under Article 2.3 of the Tennis Anti-Doping Programme."
Troicki, who reached the third round of Wimbledon this year, was ranked just outside the world's top 10 as recently as 2011.
His ban will begin immediately and will end on January 24, 2015. He must also forfeit any prize money and ranking points earned at the Monte Carlo Masters.
