Bodexpress (30-1) draws into the Kentucky Derby field in post position 20, and all horses outside Omaha Beach (13-20) will move over one position.
Morning line favorite Omaha Beach has reportedly been pulled from the race.
Omaha Beach was scheduled to come out of Gate 12, which hasn't sent off a victor since 1971, when Canonero II won from No. 12. In terms of the Triple Crown, the most momentous scratch was I'll Have Another defecting from the Belmont the day before he was to run for the Triple Crown in 2012. Porter's Derby highs and lows have been extreme - he had Hard Spun finished second in 2007, then had filly Eight Belles suffer a fatal breakdown after finishing second the next year.
Justify won the Kentucky Derby past year on his way to winning the Triple Crown.
"I'll be rooting for Roadster's connections big-time, " he said.
The revised morning-line odds from track oddsmaker Mike Battaglia issued shortly after Wednesday's announcement have priced Game Winner as the favorite at 9-2, while Roadster and Improbable are the joint second choices at 5-1.
The first leg of horse racing's Triple Crown is only a few days away, and post positions were drawn for the 20 horses in the field on Tuesday.