In two of the most unlikely stories in Kentucky Derby history, Animal Kingdom won the classic at just his fifth start and Johnny Velazquez finally captured the Run For The Roses.Velazquez had been booked to ride favoured horses in the past three runnings of the Derby only to lose them before race day to injury or illness.He picked up the ride on Animal Kingdom on Derby eve when Robby Albarado was injured."Now I pick up this one and I win the Derby. It was meant to be," Velazquez said. "It's word

In two of the most unlikely stories in Kentucky Derby history, Animal Kingdom won the classic at just his fifth start and Johnny Velazquez finally captured the Run For The Roses.

Velazquez had been booked to ride favoured horses in the past three runnings of the Derby only to lose them before race day to injury or illness.

He picked up the ride on Animal Kingdom on Derby eve when Robby Albarado was injured.

"Now I pick up this one and I win the Derby. It was meant to be," Velazquez said. "It's words you can't describe."

Not since Exterminator in 1918 has a horse won the Derby after so few career starts and not since Needles in 1956 has a horse won the Derby after a six-week lay-off such as Animal Kingdom had before starting from gate 16 of 19.

"I'm surprised," Animal Kingdom's owner Barry Irwin said.

"This horse was bucking a lot of history and it was not something we really expected. I'm overwhelmed."

Animal Kingdom covered the 1 1/4-miles (2000m) in 2:02.4 at the famous Churchill Downs track, charging up the middle of the home straight to defeat Nehro by 2-3/4 lengths with Mucho Macho Man third.

By capturing the opener in the US Triple Crown series, Animal Kingdom will try to become the first horse since Affirmed in 1978 to sweep the treble that continues in two weeks at the Preakness and concludes at June's Belmont Stakes.

"This is an amazing horse," trainer Graham Motion said.

"He's a very special horse and Johnny did a great job on him."

Velazquez finished his strange journey to a Derby triumph after losing the chance to ride Uncle Mo who was pulled from the lineup on Friday because of intestinal and stomach problems.

But after Albarado suffered a broken nose earlier in the week, Irwin and Motion made the decision to put Velazquez in the saddle in place of Albarado.

"I do really feel really bad for Robby," Velazquez said. "This is for both of us. I know you're not on it, but I know you're with me."

Archarcharch, winner of the Arkansas Derby, was taken off the track in an equine ambulance after pulling up at the wire.

He suffered a leg fracture that was not life threatening and was being prepared for surgery.

A record crowd of 164,858 jammed the historic oval to watch the equine three-year-olds battle.

Favourite Dialed In, who went off at 5-1, finished eighth after failing to stay the distance.

Animal Kingdom moved up on the outside coming off the last turn after Nehro made his outside move to challenge rail-holding Shackleford. Velazquez, a quick study on his new ride, let his horse dictate the action from there.

"We know the horses," Velazquez said. "We talk to the trainer and each other.

"I just let him find his way around. A good horse gets you out of trouble."