Curlin became the first North American thoroughbred to surpass the $US10 million ($A11.99 million) prizemoney barrier with a come-from-behind victory in the Jockey Club Gold Cup.The reigning US Horse of the Year captured his 11th victory in 15 career starts with his triumph in the $US750,000 ($A899,496) race at a sloppy Belmont Park.The win took Curlin's career earnings to $US10.24 million ($A12.28 million) dollars.The four-year-old son of Smart Strike passed Cigar, who earned 9.99 million dolla

Curlin became the first North American thoroughbred to surpass the $US10 million ($A11.99 million) prizemoney barrier with a come-from-behind victory in the Jockey Club Gold Cup.

The reigning US Horse of the Year captured his 11th victory in 15 career starts with his triumph in the $US750,000 ($A899,496) race at a sloppy Belmont Park.

The win took Curlin's career earnings to $US10.24 million ($A12.28 million) dollars.

The four-year-old son of Smart Strike passed Cigar, who earned 9.99 million dollars in 33 career starts.

"It's amazing," Curlin's jockey Robby Albarado said.

"I'm sure it is not going to hit me for a while. I'm sure this record will be broken one day, but it will take a helluva horse."

Trainer Steve Asmussen was equally proud of the horse.

"It was very emotional for me," Asmussen said.

"I was very excited and very proud of everybody involved. We had two back-to-back five million-dollar years."

Albarado kept Curlin in the middle of the pack as Wanderin Boy set the pace in the 1-1/4-mile (2000m)race.

Moving into the turn Albarado asked for more, steering three-wide toward the front.

Curlin, the 2-5 favorite, wore down Wanderin Boy (7-1) and pulled in front to win by three-quarters of a length.

"He just ran his race again and gave me that big Curlin move again on the turn," Albarado said.

"It was tremendous - and very emotional. The bar is set against him every time, but he exceeds our expectations every time he runs."

Wanderin Boy held on for second, while Merchant Marine was third.

"I got beat by the best horse, and he's an excellent horse," said Alan Garcia, who was in the irons on Wanderin Boy.

Curlin's only non-victory this year came in his turf debut at Belmont in July, when he was runner-up to Red Rocks in the Man O'War Stakes.

A showdown with reigning Preakness and Kentucky Derby champion Big Brown looms at the Breeders' Cup Classic at Santa Anita on October 25.

However, Curlin's connections have expressed concerns about the synthetic surface at the California track.