Serbian tennis player Viktor Troicki has been suspended for 18 months for refusing to submit to blood testing before the Monte Carlo Masters.
The International Tennis Federation said Thursday he broke an anti-doping rule in April by "refusing or failing without compelling justification to submit to sample collection."
Troicki was told to provide a urine and blood sample. The ITF said in a statement the 27-year-old player gave a urine sample but told the doping control officer he was ill and didn't want to give a blood sample.
The ban, by an independent tribunal, ends Jan. 24, 2015.