Hall of Fame jockey John Velazquez had his spleen removed after he was thrown from a horse during the Breeders’ Cup.

The Puerto Rican jockey was taken to the hospital on Saturday after he fell from his mount. The filly, Secret Compass, was euthanized on the track after breaking her leg during the $2 million Juvenile Fillies.

Velazquez's agent, Angel Cordero Jr., told a Santa Anita spokesman by phone that the jockey was about to be released from a Pasadena hospital after he was thrown from Secret Compass and hit the track hard during Saturday's first Breeders' Cup race when doctors discovered internal bleeding.

Cordero says Velazquez was immediately taken to surgery for the spleen removal.

The 41-year-old New York-based jockey has won most of the nation's major stakes, including 13 Breeders' Cup races.

“This is heartbreaking. Heartbreaking,” said trainer Jeff Bonde, who saddled She’s a Tiger, told the New York Daily News. “There is nothing else I can say. She is still a wonderful filly, but this is just heartbreaking.”

It was a day of mixed results for the replacement riders on the eight horses slated to have Velazquez in the saddle, with a win for Jose Lezcano aboard Wise Dan in the Breeders' Cup Mile and a pair of seconds for other jockeys earlier on the card.

The seconds included Havana, the favorite for trainer Todd Pletcher in the $2 million Breeders' Cup Juvenile, one of two Velazquez mounts taken over by 50-year-old Hall of Famer Gary Stevens.

Stevens steered Havana to the lead and what looked like a victory in the homestretch before the colt lost steam and was overtaken by trainer Bob Baffert's New Year's Day.

"It was a great try," Stevens said.

With little time for instructions, Stevens said Havana's connections kept it simple, saying nothing more than hold on to the whip.

"They just told me not to hit him," Stevens said.

Luis Saez, the first jockey to take a Velazquez mount just minutes after the accident, came even closer. Saez rode Judy The Beauty in a fierce rally in the $1 million Filly & Mare Sprint before winner Groupie Doll won by a half-length.

"I came flying, but it was too late," said Saez, who was asked to ride the Judy The Beauty for the first time just 15 minutes before the race.

It was a different story for Lezcano, who had ridden Wise Dan several times before. It showed with a win in the $2 million Mile as he rallied to beat long- shot Za Approval by three-quarters of a length.

"I really wanted Johnny to ride the horse, but Jose's done a great job, he's always picked him up when Johnny's hurt," said Wise Dan's trainer, Charles LoPresti "He didn't panic, and it worked out."

Based on reporting by The Associated Press.

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