A Kenyan sprinter was suspended from the Olympics after he received a positive steroid test.
Mark Odhiambo was provisionally suspended by the International Testing Agency on Saturday, The Associated Press reported.
He plans to challenge the decision with the Court of Arbitration for Sport, but with have to miss the men 100-meter heats Saturday.
Odhiambo gave the sample on Wednesday and the positive test was discovered on Saturday.
The test comes a day after U.S. medalist Ryan Murphy accused competitors in the 200-meter backstroke of illegally doping.
“It is a huge mental drain on me to hear I’m swimming in a race that’s probably not clean,” Murphy said. “That is what it is.”