Nitrogen, the Great Hope for Mark Casse to Conquer the Breeders' Cup Distaff

The D.J. Stable champion will look to improve on her runner-up finish from 2025 and secure the tenth victory of her career. The trainer will also saddle Measure in the same race, while Classic Q and Voyager will be among his other primary contenders at Keeneland

ELMONT, New York (Special for Turf Diario).— Nitrogen will get another opportunity to achieve glory in the Breeders' Cup Distaff (G1), a race she knows intimately and where she came close to earning her coronation a year ago. The daughter of Medaglia d'Oro, one of the cornerstone stars of Mark Casse's barn, will lead the trainer's squad in the $2,000,000 event, where an encounter of supreme quality is promised.

Bred in Kentucky by her owners, D.J. Stable, the 4-year-old dark bay filly will face her third consecutive appearance at the world championships. In 2024, she finished third in the Breeders' Cup Juvenile Fillies Turf (G1) while still maiden, while in 2025, she finished second behind Scylla (Tapit) in the Distaff.

She now returns as one of the elite older mares in the United States, boasting a career record of 9 wins, 6 seconds, and 3 thirds from 18 starts, with earnings topping $3 million.

Her progression is also remarkable for the versatility she has displayed, having secured three graded stakes victories on turf and another five on dirt.

During her last three starts she competed in New York, where she delivered top-shelf performances. The most impressive came in the Ogden Phipps Stakes (G1) at Saratoga, when she drew off by 12 3/4 lengths over her rivals while earning a 113 Beyer Speed Figure, the highest of her career.

That victory took on even greater significance as the months passed, as runner-up Fully Subscribed (Tiz the Law), trained by Chad Brown, subsequently captured three graded stakes, two of them at the G1 level.

Nitrogen also proved game enough to tackle the males in the Whitney Stakes (G1), where she finished second to Sovereignty (Into Mischief), the reigning Horse of the Year.

Her final prep prior to the Breeders' Cup was the Beldame Stakes (G2), run on September 25 at Belmont Park, where she controlled matters wire-to-wire to score by 2 3/4 lengths under regular pilot José Ortiz.

"She arrived in Kentucky on Wednesday and has already worked at Keeneland. She is doing very well," noted Casse, a member of both the U.S. and Canadian Halls of Fame.

"I liked her race in the Beldame very much, as well as the timing of it. Everything points to a great showdown between her and Chad Brown's filly."

One of the most intriguing aspects of the Distaff will be the pace scenario, given the presence of several contenders with early speed. However, Casse has no intention of making major tactical adjustments with Nitrogen: "She'll run fairly close to the pace. Maybe we'll try to relax her a little, but we aren't going to take a big hold of her. We'll let her run her race," he explained.

The trainer's confidence is also bolstered by a decision made by her owners: Nitrogen will remain in training for 2027, provided she emerges from the Breeders' Cup in good shape.

"That is the plan, provided she comes out of the race healthy," he confirmed. "Our sport needs its stars, and she is definitely a star. I credit the Green family for the sportsmanship they continue to display."

The prospect of continuing to see the 2025 champion 3-year-old filly on the track is welcome news for American racing.

Measure, the barn's second Distaff weapon

Casse will also saddle Measure in the Distaff, a 3-year-old daughter of Essential Quality owned by Gary Barber, Bridlewood Farm, and Eclipse Thoroughbred Partners.

In contrast to Nitrogen, Measure typically turns in her best running from off the pace, a trait that could play into her hands should the early leaders set a grueling pace.

The filly has finished in the top three in her last four starts, including three consecutive G1 events. She was third behind stablemate Counting Stars (Honor A. P.) in the Coaching Club American Oaks (G1), second by a neck to My Gun's Loaded (Gun Runner) in the Alabama Stakes (G1), and third in the Cotillion Stakes (G1), where she suffered traffic trouble as she made her move. "We've always had a very high opinion of her. I wasn't disappointed in her early efforts this year, but I felt she needed to settle in and find races with more tempo," Casse explained.

"Her Alabama was extraordinary, and she was very unlucky in the Cotillion. The 1800 meters will suit her extremely well, as will a fast pace, which looks like what we'll get in the Distaff."

Manuel Franco will retain the ride.

Classic Q and Voyager also in the mix

Casse's Breeders' Cup representation will not be limited to the Distaff. Classic Q, a 4-year-old gray daughter of Classic Empire, will ultimately target the Breeders' Cup Filly & Mare Turf (G1), after her connections gave serious thought to facing males in the Mile.

The mare has won three of her six starts in 2026, including the Distaff Turf Mile (G2), the Just a Game Stakes (G1), and the recent First Lady Stakes (G1), where she prevailed by a nose over Lush Lips (Ten Sovereigns) at Keeneland.

"We thought about running in the Mile, but we ultimately decided to keep her against the fillies," Casse pointed out. "With the 1900 meters of the Filly & Mare Turf, I imagine she will likely go out and run near the lead."

Javier Castellano will take over for John Velazquez, who is committed to ride Gimme a Nother(Gimmethegreenlight).

Another representative for D.J. Stable will be Voyager, a daughter of Justify set to compete in the Breeders' Cup Juvenile Fillies Turf (G1).

After a pair of second-place finishes on dirt, including one in the Schuylerville Stakes (L), the filly made the switch to grass and secured her maiden victory at Saratoga over 1700 meters with two turns. She subsequently confirmed her turf affinity by winning the Natalma Stakes (G1) on September 12 at Woodbine by 1 1/4 lengths.

"I was very pleased she was able to win around two turns at Saratoga, because giving her that experience was important," Casse explained. "Then we brought her back over a one-turn mile in the Natalma, but she is a very versatile filly. That performance was very strong, and she is training exceptionally well."

Facteur Cheval joins the barn

While preparing his primary contenders for the Breeders' Cup, Casse received additional satisfaction from Facteur Cheval, who scored in his first start under his care.

The seasoned 7-year-old gelding by Ribchester scored by half a length in an allowance race over 1700 meters at Keeneland, ridden by Irad Ortiz Jr.

Winner of the 2024 Dubai Turf (G1), Facteur Cheval has accumulated over $5.7 million in purse earnings with a career record of 7 wins, 7 seconds, and 6 thirds from 28 starts. He was previously trained by Jerome Reynier and came off a sixth-place effort in the Mint Millions (G3) at Kentucky Downs.

"Barry Irwin mentioned to us that it was important to get him engaged early in the race," Casse explained.

"We told Irad to be aggressive right from the start and that made all the difference. It's a privilege to have a horse of his caliber in our barn." His next objective will be the River City Stakes (G3), scheduled for November 7 at Churchill Downs.