Constitution Hill is set to undergo a rigorous assessment of his ambitions for the top tier of flat racing when he lines up for the William Hill September Stakes at Kempton Park on Saturday. The nine‑year‑old former hurdling star will be partnered by the up‑and‑coming jockey Billy Loughnane, marking a fresh partnership that could prove pivotal for his flat campaign.

Since making the switch from hurdles to the flat, the Nicky Henderson‑trained former superstar has been unbeaten, winning his first two starts over the new discipline. However, the Group Three contest at Kempton – a right‑hand, oval track known for its stiff testing mile‑and‑a‑half distance – represents a significant step up in class and will be a true gauge of his staying power and adaptability.

In his brief flat career, Constitution Hill has already been ridden by two of the sport’s leading riders, Oisin Murphy and Ryan Moore. The latest BHA entry list for the weekend shows Billy Loughnane’s name alongside the Seven Barrows‑trained runner, confirming the change of tack.

Loughnane’s agent, Tony Hind – who also manages Ryan Moore – explained the switch, noting that Henderson was happy for the championship‑leading jockey to be replaced while Moore was committed to a ride in America. "His first choice was Ryan, who is riding in the United States," Hind said. "So I offered him Billy, who is definitely riding in the Sirenia Stakes, and Nicky confirmed this morning that he was fine for Billy to take the mount." The field for the September Stakes is strong and diverse.

Leading the opposition is George Scott’s dominant Coronation Cup winner Bay City Roller, a horse that is being pointed towards the Prix de l'Arc de Triomphe later in the season. Saeed bin Suroor has entered the Group One‑winning Tornado Alert, with Oisin Murphy slated to ride, while the ever‑reliable Dubai Future also makes the start. Ralph Beckett will field last year’s Great Voltigeur winner Pride Of Arras, adding further depth to the mile‑and‑a‑half contest. Owen Burrows‑trained Gethin and Joseph O'Brien’s Small Fry are also among the fourteen possible contenders, each offering a different tactical angle for the race.

Gethin, who last appeared in the Coral‑Eclipse at Sandown in early July, disappointed his connections then, but Burrows remains optimistic that the horse will rediscover his true form at Kempton. The trainer sees the September Stakes as a potential stepping stone toward an Arc campaign, should the horse respond positively. Callum Rodriguez, who has piloted the Wathnan Racing‑owned grey to each of his three career victories, is set to return to the saddle for this race. James Doyle is expected to ride the Wathnan stable’s entry in the Sprint Cup at Haydock later that afternoon, meaning Rodriguez will have a full day of top‑level riding.

Burrows told Sky Sports Racing: "He's in good shape. Callum had a sit on him last Wednesday because we thought James would be up at Haydock for the Sprint Cup and he was very happy with him. It's been a bit frustrating we've had to sit on him during the hot months, but we knew we had no issues worrying about weather for this race and I'm looking forward to getting him back out. He was fine after the Eclipse.

If you look at the sectionals it was pretty hard for the first four furlongs and quickish ground as well, hence why we didn't want to go again on it." When asked about the prospect of taking on Constitution Hill, Burrows added: "He obviously brings a nice dimension to the race and I'm sure it will add plenty at the gate, but like any trainer I just want to beat all the opposition, so if he's in it then he's included in that. It will be interesting, but I'm hopeful. Wathnan bought him with an Arc in mind, so if Saturday goes well I dare say that will be his next step." The September Stakes will therefore serve as a crucial litmus test for Constitution Hill’s transition from hurdling to staying flat races.

A strong performance could cement his status as a genuine dual‑code champion and set the stage for a potential run in Europe’s premier middle‑distance contest, the Arc. Conversely, a lackluster showing would prompt Henderson and his team to reassess the horse’s optimum distance and surface preferences. Racing enthusiasts can stay up‑to‑date with the latest developments, interviews, and expert analysis by following Sky Sports Racing on mobile platforms, ensuring they never miss a story from the world of thoroughbred racing.