Maximum Security was beaten in his first start.
The colt lined up in Monmouth Park in New Jersey on Sunday (Monday AEST) as the overwhelming favourite but was defeated by King For A Day.
Before assuming control to win by a length, with King For A Day stalking him he stumbled slightly at the beginning but got to the guide.
“I think the next race will be better,” Maximum Security’s trainer Jason Servis said.
“We needed to find that out of the way. I was happy to get it out of the way even though he got beat.”
It marked the first time and the stumble could have been the difference.
“It was a difficult week,” Servis, who had debated whether to run Maximum Security since he wasn’t convinced he was ready, said.
“He was feeling pretty good this afternoon. He jumped and kicking. But the stumble hurt us much.”
King For A Day was the second favorite after his triumph in the Sir Barton at Pimlico on the Preakness undercard.
Founded by Gary and Mary West, Maximum Security ended 1-3/4 lengths in front of Country House in the Kentucky Derby but was disqualified by Churchill Downs stewards for hindrance to Preakness winner Battle of Will.
The Wests are challenging the Kentucky Derby disqualification in court.
Maximum Security is expected to run in the Haskell Invitational.