Multiple Grade 1 winner Shackleford, the 2-1 morning-line favorite, has been scratched from Saturday's $500,000 Forego.
Trainer Dale Romans said the 4-year-old colt has coughed recently and that he won't start him unless he is 100 percent.
“He had a little cough last week and a little cough this morning, so we’re going to play it safe,” Romans said.
Shackleford has won five of 17 career starts, including the 2011 Grade 1 Preakness and the 2012 Grade 1 Metropolitan Handicap. In his most recent start, he was last of eight in the Grade 1 Alfred G. Vanderbilt Handicap on August 5 at Saratoga. The chestnut son of Forestry has earned $2,744,047.
Romans said he expects the colt will recovery quickly and be able to have a prep race prior to running in the Breeders' Cup at Santa Anita.