One day after losing Kentucky Derby and Preakness winner Big Brown to a career-ending hoof inj­ury, Breeders’ Cup officials breathed a hugh sigh of relief.

Jess Jackson, majority owner of Curlin, confirmed Tuesday that he will enter the reigning Horse of the Year in the $5 million Breeders’ Cup Classic.

Pre-entries for all 14 Breeders’ Cup races, to be held Oct. 24 and 25 at Santa Anita Park in Arcadia, Calif., were due on Tuesday. The entire list will be announced Thursday.

“I think I owe it to the horse,” Jackson said during a national tel­econference. “Curlin tells us he’s fit and ready, and he loves to compete. When a top athlete is ready, they want to play, and every sign Curlin has given us indicates that he’s ready now.

“Racing is blessed to have such a magnificent athlete among us. He’s brilliant and durable, and always shows up, always gives his best. We’re hoping for a repeat of last year’s Classic, but he’s already a champion. He doesn’t need to win. If he did, it would be the cherry on top of our sundae for this year.”

A 4-year-old son of Smart Strike, Curlin has won 11 of 15 career starts, including the Grade I Woodward at Saratoga Race Course and the Grade I Jockey Club Gold Cup last month at Belmont Park, which made him the first North Amer­ican-based thoroughbred to top $10 million in career earnings.

The Classic had been billed as a showdown between Curlin, the world’s best older horse, and Big Brown, the country’s top 3-year-old. Big Brown was injured during a Monday morning workout at Aqueduct and was retired from racing.

“My family and I were saddened to learn of Big Brown’s career-ending injury,” Jackson said. “I’ve always said what a great horse he is, and he brought a lot of energy and excitement to the industry. It’s unfortunate, and I’m disappointed that Big Brown and Curlin will never compete against each other.”

Breeders’ Cup president and CEO Greg Avioli was thrilled to hear of Curlin’s plans. There had been some hesitation from Curlin’s connections about running on the synthetic surfaces that are mandated for all of California’s tracks, particularly at Santa Anita, which only recently installed a new Pro-Ride surface.

“I can’t tell you, on behalf of the Breeders’ Cup and racing fans around the world, how happy we are,” Avioli said. “Curlin has established himself as one of the great champions of all time.

“What we try to do at the Breeders’ Cup is get the best horses the opportunity to compete against each other. Mr. Jackson has given everyone the opportunity to witness greatness on an international scene.”

Curlin shipped from the Oklahoma training track in Saratoga Springs to Santa Anita last month, and on Monday, had his second workout over the track. He was clocked in :59.11 for five furlongs, the third-fastest of 54 horses at the distance.

“Everything is a go,” Jackson said. “He showed yesterday that he can handle the track. I’m very pleased he’s going to run, and we’ll love to see the competition. We hope that everyone will come, and it will be a full field.”

Trained by Steve Asmussen, Curlin, who did not run as a 2-year-old, has never been worse than third in any start, winning the 2007 Classic at Monmouth Park.

This year, he has also won the $6 million Dubai World Cup and Grade I Stephen Foster, and was second between past Breeders’ Cup winners in the Man o’ War July 12 in his lone career try on grass.

“The Classic would add one more dimension to his legacy, which I think he’s already earned,” Jackson said. “He loves to run, and he rarely disappoints. He’s a hero for thousands of fans, but especially me.”