Rebel Stakes (G2) winner Sierra Sunset is out of contention for the Triple Crown following the discovery of a hairline fracture in his left front ankle.

The California-bred Bertrando colt scored a three-length win in the Rebel on March 15 after finishing second to Denis of Cork in the Southwest Stakes (G3) for Northern California-based trainer Jeff Bonde.

Sierra Sunset was scheduled to stay at Oaklawn for the Arkansas Derby (G2) on April 15. The injury will not require surgery, and he is expected to be out of training for 60 to 90 days.

“We understand this is part of the game, but of course this is very disappointing,” Bonde said. “He is a sound colt, he has danced every dance, he had a clean trip in the Rebel, and he appeared to come out of the race fine. The first set of X-rays were clean, but when we took a second set, we found the hairline.”

Sierra Sunset won the Bay Meadows Juvenile and California Cup Juvenile as a two-year-old. He has won four of 11 starts and earned $428,696 for owners Philip Lebherz, Al Mariani, George Schmitt, and Carol Wirth Trust.