Trinidad and Tobago sprinter Kelly-Ann Baptiste, who won a world 100 metres bronze medal in 2011 and was a real prospect for Moscow, has tested positive for a banned substance, the Trinidad Express newspaper reported on Saturday.
Baptiste, 26, has returned home from the world championships where she was due to run in the first round of the 100m heats on Sunday morning.
"She has voluntarily withdrawn from the competition and is heading back to her base," the newspaper quoted Trinidad and Tobago team manager Dexter Voisin as saying.
Voisin did not say that Baptiste had tested positive but the newspaper said a reliable source had confirmed it.
Voisin said another Trinidad & Tobago woman sprinter, Semoy Hackett, 24, had also withdrawn from the championships and returned home voluntarily.
"They both left this morning," said Voisin.
Baptiste, the third fastest woman this year over 100m, hails from the same training group of former world sprint champion Tyson Gay of the United States, who has returned two positive tests for an undisclosed banned substance.
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