sentences:  On February 21, 2007, Sergey Shiryayev of Russia was involved in pre-competition testing for doping with a blood and urine sample.The blood sample in the "A-test" turned out high in hemoglobin, so the "B-test" was evaluated and confirmed to contain EPO.Shiryayev, who had his best finish of 11th in the 15 km event at the championships, was subsequently disqualified on March 4, 2007.