A newly revamped Arc Trials day takes centre stage on Sunday, a week earlier than in previous years. The Prix Vermeille is joined by a second Group 1 on the card in the Prix du Moulin, while the Prix Niel and Prix Foy are well-established trials for next month'sQatar Prix de l’Arc de Triomphe.
When is Arc Trials day?
Arc Trials day takes place on Sunday, September 7 at Longchamp, four weeks before the Arc on October 5. The card, officially branded as Qatar Arc Trials day, begins in the early afternoon and offers trainers the chance to test their stars over the same course and distance as Europe’s premier race.
It regularly attracts leading British and Irish challengers, with several past Arc winners having used the day as their launchpad to great things.
What are the big races?
There are three recognised Arc trials on Sunday’s card: the Prix Vermeille, Prix Niel and Prix Foy.
Traditionally, this Sunday has been headlined by the Group 1 Prix du Moulin, but the three Arc trials have been brought forward a week to enable a bigger gap between the rehearsal and the big race, a decision which also helps give the meeting a greater platform away from a regular clash with the final day of the St Leger fixture at Doncaster and the second day of the Irish Champions Festival at the Curragh.

Longchamp: stages Arc Trials day on SundayCredit: Edward Whitaker
The Vermeille, Niel and Foy are run over the same course and distance as the Arc. The Vermeille is a Group 1 for fillies and mares, while the Niel and Foy are Group 2s, with the former for three-year-olds and latter for horses aged four and older.
Topping the prize-money table is the Group 1 Prix du Moulin, worth an upgraded €800,000 from €450,000 and staged over a mile. The last British-trained winner was Dreamloper, trained by Ed Walker, in 2022 and it has also been won by the likes of Baaeed and Ribchester in the last decade.
Who could run?
Wednesday's forfeits stage will provide greater clarity, while there is also a supplementary stage on Thursday.
Aidan O'Brien said on Monday it is "very possible" Pretty Polly Stakes and Nassau Stakes winner Whirl will run in the Prix Vermeille before a possible Arc run. Other possibles include You Got To Me, who recently moved to Adrian Murray in Ireland for Amo Racing, the Christophe Ferland-trained Aventure and ante-post Arc favourite Kalpana, although she is set to run in the September Stakes at Kempton on Saturday instead.

Ed Walker-trained Almaqam is set to run in the Prix FoyCredit: Getty Images
In the Prix Foy, Joseph O’Brien has the JP McManus-owned Trustyourtinstinct, a gelding who cannot contest the Arc but could bid for a first Group 2 success. O’Brien has a strong hand and the sole representative from Ballydoyle is likely to be Los Angeles.
- Aidan O'Brien reveals preferred starting team for the Arc - and says we haven't even seen the best of Minnie Hauk yet
Ed Walker has outlined plans for Almaqam to run in France to help determine his Arc credentials in the Prix Foy, while Wathnan’s Map Of Stars is another likely to line up. Sosie is expected to also compete, alongside Japanese challenger Byzantine Dream, who will be partnered by Oisin Murphy.
The Prix Niel could feature the William Haggas-trained Merchant, who will look to take advantage of the “win and you’re in” berth for the Arc. Possible rivals include the Francis Graffard-trained Daryz, Ralph Beckett-trained Amiloc and Juddmonte’s Windlord.
Roger Teal is determined to keep chasing Group 1 success withDancing Gemini in the Prix du Moulin, while the French representatives could include Facteur Cheval, Zarigana and Godolphin's Tribalist, who won the race 12 months ago.
French 1,000 Guineas winner Henri Mattise also holds an entry for the Moulin, along with stablemate Officer.
How have trials winners fared in the Arc?
Last year’s Prix Vermeille winner Bluestocking followed up in the Arc, becoming the seventh horse to win both races in the same year, and the first since the magnificent Treve in 2013. She then finished fourth in the 2014 Vermeille before winning again at Longchamp, but was denied in her attempt to complete the double again in 2015 when beaten by Golden Horn in her historic Arc hat-trick bid.
Left Hand in 2016 was the last Vermeille winner to move on to the Arc the following month, but she could only finish 12th in the big one.
The Prix Niel has produced 12 Arc winners in the same year, most recently with Rail Link for Andre Fabre in 2006. Sottsass won the Niel in 2019 before triumphing in the Arc the following season.
As for the Prix Foy, the most recent horse to complete the double was Fabre’s Waldgeist, who denied odds-on favourite Enable in the 2019 Arc. Before him, the feat had only been achieved by Allez France (1974) and Sagace (1984).
What's the betting for the Arc?
Qatar Prix de l'Arc de Triomphe (3.00 Longchamp, October 5)
William Hill: 6 Kalpana, Whirl, 8 Minnie Hauk, 14 Croix Du Nord, 16 Aventure, Sosie, 20 Byzantine Dream, Estrange, Gezora, Leffard, Los Angeles, Quisisana, 25 bar.
Read these next:
Aidan O'Brien reveals preferred starting team for the Arc - and says we haven't even seen the best of Minnie Hauk yet
Estrange to run in the Arc or on Champions Day at Ascot after being ruled out of Sunday's Prix Vermeille
Aidan O'Brien: Christophe Soumillon to play a major role for Ballydoyle this autumn in Ryan Moore's injury absence

Sign up to receive The Ante-Postman, Robbie Wilders' top weekly newsletter. Get weekend tips, festival fancies and big-race selections delivered straight to your inbox.