Key quotes and what to look out for on a day rich with intrigue and pointers
The Vermeille, Foy and Niel. Three races with three very different profiles in terms of their Arc credentials, although this year's line-ups could turn conventional wisdom on its head in terms of which proves the best trial for Europe's richest race in three weeks' time.
The Qatar Prix Vermeille has a fine recent record in terms of finding the Arc winner, with Zarkava setting the ball rolling a decade ago and four of the last ten winners coming out of the race – Solemia and Treve were beaten in the Vermeille but still triumphed on the day that mattered most.
This year's line-up includes only two fillies who hold the Arc engagement – Kitesurf and Zarkava's daughter by Frankel, Zarkamiya – and the race looks to be one where connections have eyes for the here and now rather than three weeks' time.
The Qatar Prix Foy-Arc double has been achieved only twice in 44 years but its relevance is boosted this time by the presence of the returning Capri, as well as a trio of Andre Fabre runners who all have legitimate claims of finishing in the money on October 7, when the big race will be shown live on ITV.
Waldgeist has shown the best level of form among the Fabre runners this season and in most bookmaker lists is the shortest-priced Arc contender on show on Sunday.
Talismanic has a recent win under his belt and is the choice of Mickael Barzalona, while Cloth Of Stars is the one who needs to secure his place on the team, despite finishing second to Enable at Chantilly last year.
Fabre will not have any of his runners at concert pitch and, with the added interest of a first European appearance by Japanese challenger Clincher, it should be a race worth careful review.
That might mean it will take something special to shake the market up, although all bar Royal Youmzain and Bruntland are entered and there is certainly room for an Arc market springer among the three-year-old colts.
What They Say
Andre Fabre, trainer of Kitesurf
If she brings her best level of form to this race she'll go close. She's coming to this off a good Group 2 win at Deauville and the form was given a boost when the third, God Given, won at Doncaster this week.
Alain de Royer-Dupre, trainer of Zarkamiya
She isn't one of the leading contenders on paper but is in great condition and loves good ground. If she's placed we'll be happy. She likes Longchamp and the other day at Deauville I don’t think she had properly recovered from the effort of her Listed win.
Aidan O’Brien, trainer of Bye Bye Baby and Magic Wand
We've been happy with Magic Wand since her run in the Yorkshire Oaks and she seems in good form. Bye Bye Baby is a solid filly who gets the trip well.
Jean-Pierre Carvalho, trainer of Well Timed
It won’t be easy because it’s the first try away from home, over this trip and against older horses. Against that, it’s not the deepest Vermeille and she's the only Group 1 winner in the line-up.
Aidan O’Brien, trainer of Capri
He's had only the one run this year and has had a long break. He was almost ready to start back around the time most of our horses were under the weather, so we decided to wait a bit longer. We're happy with him but we expect he'll improve a lot for the run. The present plan is to go for the Arc.
Andre Fabre, trainer of Cloth Of Stars and Talismanic
Talismanic is happy and well. This is a prep for the Arc and he's discovering Longchamp for the first time. Cloth Of Stars is making his comeback after a fine run [fourth to Waldgeist] in the Grand Prix de Saint-Cloud. The saddle slipped turning for home and the jockey felt he was travelling very strongly at the time but it completely unbalanced him. He's in good order. This race will tell us where he goes next.
Hiroshi Miyamoto, trainer of Clincher
The owner was very keen and called me straight after the Tenno Sho and said, 'We’re going for the Arc'. He's at his best on heavy ground but finished fourth in the Japanese 2,000 Guineas on a fast surface so it doesn’t pose a problem.
Andreas Wohler, trainer of Royal Youmzain
I was keen to run him back against three-year-olds after his good run in the Grosser Preis von Berlin. We didn’t plan to make the running last time, it was just the circumstances of the race, and hopefully we won’t need to again.
Pia Brandt, trainer of Neufbosc
He's fairly straight and I'd put him at 85 or 90 per cent readiness. I'm pleased the German horse is in there because he won't want a slowly run race – it should be a good prep run for the future.
Pascal Bary, trainer of Naturally High
He ran very badly in the Jockey Club and was pretty sick afterwards. His work has been good and I expect him to run very well.
Charlie Appleby, trainer of Brundtland
He wouldn't excite you at home, he just gets the job done, which is similar to his racing style. It was a bit of a rush before his comeback, which is why he ended up going to Clairefontaine. I was short of options to get a prep run into him before some of these trials. He's definitely come forward on the fitness level.
Aidan O'Brien, trainer of Hunting Horn
He ran very well when third in the Belmont Derby in July and then had a bad draw in the Secretariat last month. We've been happy with him since and he's in good form.
Read exclusive daily previews from 6pm at racingpost.com/news