LOS ANGELES, United States (AFP) – Trainer Bill Mott was still feeling his way through complicated emotions Sunday, a day after his Country House won the Kentucky Derby when first-past-the-post Maximum Security was disqualified.

The sensational outcome, a first in the 145-year history of the Kentucky Derby, promises to rumble on throughout US flat-racing’s Triple Crown season, with Maximum Security owner Gary West refusing to rule out an appeal.

“I feel terrible that I have to apologise for winning,” Mott, who claimed his first Derby victory, said as Country House was paraded for photographers at Churchill Downs on Sunday morning.

“I really feel terrible for the connections, for the owners. I hate to sit there and apologise, saying something as foolish as “I’m sorry I won.”

Maximum Security, with Luis Saez in the irons, swept across the finishing line 1 1/2 lengths in front of 65-1 long shot Country House.

But Maximum Security had briefly veered from the rail as the field turned for home, and after an agonising 20-minute stewards’ inquiry, was judged to have impeded other horses and was dropped to 17th in the 19-horse field.

Questions lingered over why the stewards didn’t immediately indicate an inquiry was underway, instead of waiting for objections from Country House jockey Flavien Prat and the rider of Long Range Toddy, Jon Court.

Others wondered why the stewards never answered questions from the press about the decision, instead delivering only a prepared statement.

Marc Guilfoil, executive director of Kentucky Horse Racing Commission, told the Louisville Courier-Journal that he thought the decision would stand up to any challenge.

War of Will had to be checked hard to avoid a collision with Maximum Security on the sloppy Churchill Downs track, and stewards found that Long Range Toddy and Bodexpress were also affected.

“I agree with the stewards 100 per cent. It was the right call and the correct call. It wasn’t a popular call, but we avoided a complete catastrophe there.”

In 1968 Dancer’s Image was disqualified as the Kentucky Derby winner over a failed drug test, with Forward’s Pass inheriting the win in a decision that led to years of legal battles.

“I don’t even want to think about that,” Mott said, although he knew the controversy wouldn’t die down soon.

“They’ll be talking about this to the next Kentucky Derby and the one after that, and probably 10 Kentucky Derbys,” he said.