Can Aidan O'Brien's Queen's Vase winner Illinois emulate some high-class stablemates in the Grand Prix de Paris?

It could be argued the market for the Qatar Prix de l'Arc de Triomphe is due a shot in the arm, with Derby winner City Of Troy seemingly being aimed elsewhere and connections yet to fully commit to plans for Prix du Jockey Club hero Look De Vega.

Irish Derby winner Los Angeles is the most obvious contender among Coolmore's clutch of potentials but in Delius, they have a largely unexposed colt who has created a visual impression in three starts which outstrips what he has formally achieved.

The fact he is from a Jean-Claude Rouget yard that has produced two of the last four Arc winners has injected added enthusiasm for him ahead of a Grand Prix de Paris, which connections seemed reluctant to tackle initially, but which could now catapult the son of Frankel into the upper reaches of Europe's three-year-old rankings.

Unbeaten Delius returns after winning the the Group 3 Prix du LysCredit: Racing Post/Scott Burton

Aidan O'Brien had four possibles for the race at the start of the week but has declared only Queen's Vase winner Illinois, meaning the owners have an insurance policy in case Delius is found wanting, as well as a reasonable guarantee the race won't become a crawl.

Standing in their way are two horses proven at Classic level, with Sosie running an excellent third to Look De Vega in a Jockey Club where, after enjoying a dream run next to the rail, he took a little while to see clear daylight in the straight.

Sosie looks likely to enjoy the extra furlong and a half, a comment that is arguably less of a certainty with Tamfana, who may have paid late on for her early exertions in the Prix de Diane over 1m2½f and looks likely to be ridden more cautiously by Oisin Murphy.

Before that the daughter of Soldier Hollow produced a telling finishing kick to be fourth in the 1,000 Guineas and the €15,000 paid to supplement her will be money well spent if David Menuisier can get a firm steer on what her best trip is.

Tamfana and Oisin Murphy ahead of the Prix de Diane Longines Credit: Racing Post/Scott Burton

Mondo Man has also been supplemented after rallying form almost impossible positions to be fifth in the Jockey Club and fourth to Calandagan at Royal Ascot, although he'll surely need to stay in touch early on for that acceleration to be a factor.

Ground conditions

After a prolonged dry period Longchamp took 11 millimetres of rain overnight on Thursday, easing the ground to 3.6 (souple). Although temperatures have dropped, officials expect that to dry back to 3.4 (bon souple) by Saturday evening, which will be no worse than good in GoingStick terms.

What they say

Mikel Delzangles, trainer of Saganti
He’s been well since the Lys and I think he’s still progressing. He is up against the horse that beat him last time but I expect a good run. Quicker ground didn’t seem to bother him last time, although there is rain about, so we’ll see how the track rides.

Jean-Bernard Roth, assistant to Jean-Claude Rouget, trainer of Sibayan and Delius
Sibayan comes here off the back of a win in the Listed Derby du Midi at Bordeaux in heavy ground. That was over 1,900 metres but the surprising thing about this colt is that he seems to handle any kind of surface. The main question with him is the distance, which he tries for the first time. He has run well before at Longchamp and he is a big, strong horse who has a great stride on him, so we think this task should suit him, though he has to prove he can compete at this level. Delius is beginning to gain in maturity and he is another big, backward colt. Christophe Soumillon rode him for the first time in the Prix du Lys and he feels, as do we, that he has real potential in the future, though he remains quite raw. He worked well on the racecourse at Deauville on Tuesday and I think he should give us a good pointer to the future.

Aidan O'Brien, trainer of Illinois
He won nicely at Royal Ascot and we were delighted with him there. He seems to have bounced out of the race well so we decided to bring him over to France for this.

Joakim Brandt, joint-trainer of Mondo Man
He has progressed all year and, although he was quite highly strung early in his career, he has gone the other way now and is almost too relaxed early in his races. He really finished off his races well both at Chantilly and at Ascot and I hope he can do the same again. He is a tough horse who takes his racing well.

Carlos Laffon-Parias, trainer of Internaute
I think he’ll enjoy the step up in trip. To me he looks to have a place chance, though winning might be a little beyond him unless he really improves for the extra distance.

Sosie (white sleeves) chases home Look De Vega in the Qatar Prix du Jockey ClubCredit: AFP via Getty Images

Andre Fabre, trainer of Sosie
I think the extra distance will be in his favour as well Longchamp's Grande Piste. He ran well but he lacked a bit of maturity in the Jockey Club and the race will have done him good. I'm expecting a good run.

David Menuisier, trainer of Tamfana
It makes sense to try her over a mile and four and if it doesn’t pan out, we can forget the Arc and aim at something else. We have nothing to lose and whatever happens, we’ll either win or we’ll learn. For once I haven’t looked at the weather forecast because the filly goes in any ground.

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