(LOS ANGELES) -- The California Horse Racing Board has suspended Doug O'Neill, the trainer of Triple Crown-hopeful "I'll Have Another," for 45 days after one of his horses tested positive for high levels of carbon dioxide in 2010.
O'Neill, who has professed his innocence, will not begin serving the suspension until July 1. The delay will enable him to train the Kentucky Derby and Preakness winner in anticipation of the Belmont Stakes on June 9, where I'll Have Another will attempt to become the first Triple Crown winner since Affirmed in 1978.
The horse in question, Argenta, tested positive after a race at Del Mar in August 2010.
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