Breeders' Cup Distaff: Nitrogen's rest may be brief, Casse says

Most horses might take a well-deserved break after the biggest victory of their career, but Nitrogen is far from a typical horse. Trainer Mark Casse said the only time he has ever seen her anxious is when he has tried to rest her, so her time off will likely be brief following a commanding victory in the $2 million Breeders’ Cup Distaff on Saturday at Keeneland.

“She’s going to go to Ocala, probably give her a couple weeks off, but she doesn't like time off,” Casse said. “Some horses just can't take time, so we'll see. We’ll try to get her out and let her enjoy herself.”

With a powerful kick under Jose Ortiz, Nitrogen took over at the top of the stretch in her third attempt at a Breeders’ Cup victory. The 3-5 favorite was challenged late by Fully Subscribed, but the Chad Brown-trained second choice never managed to seriously contend. Nitrogen won by two lengths and earned a 95 Beyer Speed Figure.

Nitrogen at the end of last year could have retired as a 3-year-old and still gone out a star, having won five graded stakes, including the Grade 1 Alabama and three races on turf. She finished in the money in two Breeders’ Cup events, the 2024 Juvenile Fillies Turf and 2025 Distaff, showing immense talent and versatility.

Since June, however, the filly has put together four starts that have made her a modern legend. Her only defeat in that span came against male rivals in the Grade 1 Whitney, when she finished second behind Sovereignty, the dominant winner of the Breeders’ Cup Classic on Saturday.

“It certainly enhanced her résumé, for sure,” Jon Green, co-owner of D J Stable, said. “And really, first through last in the Whitney, every horse in there was a top horse in the division. We certainly didn't scare anybody away from the Whitney. But that being said, I thought that was a seminal moment in Nitrogen’s career, the fact that she took on the best in the world and ran the way that she wanted to run.”

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Between her 12 3/4-length victory in the Grade 1 Ogden Phipps, for which she earned a 113 Beyer Speed Figure, leisurely score in the Grade 2 Beldame, or championship victory on Saturday, Nitrogen has firmly established herself as the undisputed leader in her division. It might be time to try another.

Casse and Green have both already named the Breeders’ Cup Classic at Belmont Park next year as a long-term goal for their filly, and the trainer said an unorthodox 2027 schedule could include several starts against male rivals. That could start with the Grade 1 Pegasus World Cup at Gulfstream Park in January.

“If she trains really good, we may aim for the Pegasus, yeah,” Casse said. “But it's going to be a different path, a path that's going to include more racing against the males, I would say.”

Casse said he might have tried the Classic this year, but the owners decided early to carry on with her as a 5-year-old, giving him time to get a Breeders’ Cup victory before trying something bigger. As he put it, the next goal is to get her in the Hall of Fame.

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