Keen Ice, best known for upsetting Triple Crown winner American Pharoah in the 2015 Travers Stakes, has a minor injury that will prevent him from running in the $6 million Breeders’ Cup Classic on Nov. 4 here at Del Mar. Because the Classic was scheduled to be the final career start for Keen Ice before he goes to stud next year at Calumet Farm, he has been retired.

Keen Ice was scheduled to have his final work for the Classic on Friday at Belmont Park.

“He’s got a wrenched ankle and there’s not time to let it quiet down,” his trainer, Todd Pletcher, said Thursday. "We’ve got to breeze now, trying to make a race on the other side of the country against the best horses in the world. It’s not shaping up right. He’s accomplished everything he’s accomplished, he’s already got a home at Calumet, so hopefully he goes on and has a successful stallion career.

Keen Ice, 5, won 3 of 24 starts and $3,407,245. In addition to the Grade 1 Travers, he captured the Grade 2 Suburban in July at Belmont Park.

Keen Ice was stakes-placed in numerous major races, including the Grade 2 Remsen at age 2, the Grade 1 Belmont Stakes and Haskell at age 3, and the Breeders’ Cup Classic at age 4. Had he made this year’s Classic, it would have been his third straight appearance in that race. He was fourth in 2015 when trained by Dale Romans and third last year after being transferred to Pletcher.

In his two most-recent starts, Keen Ice was second to Gun Runner in the Grade 1 Whitney at Saratoga and second to Diversify in the Grade 1 Jockey Club Gold Cup at Belmont Park.

Keen Ice was originally owned by the Donegal Racing partnership run by Jerry Crawford. Calumet, owned by Brad Kelley, bought into Keen Ice at the beginning of this year. Keen Ice raced this year for Donegal and Calumet.

Keen Ice is by Curlin and is out of the Awesome Again mare Medomak. He was bred in Kentucky by Glencrest Farm.

Jose Ortiz, the nation’s leading rider by purse earnings this year, had ridden Keen Ice in his last three starts and was scheduled to ride him in the Classic, so he is now without a mount for the richest of the Breeders’ Cup races.

Pletcher does not have another horse in the Classic.

There were 14 horses pre-entered in the Classic on Wednesday. The field could be reduced further, as Cupid is more likely to run in the Dirt Mile on Nov. 3, and Diversify is not certain to travel from New York.

--additional reporting by David Grening