Christophe Soumillon has declined to offer further comment on the extraordinary incident on Friday when he elbowed his fellow rider, Rossa Ryan, from the saddle during a race at nearby Saint-Cloud. Controversy over Soumillon’s continued presence at Longchamp this weekend is unlikely to subside, however, before his ride on Vadeni, the French Derby winner, in the Prix de l’Arc de Triomphe on Sunday.

“I don’t speak any more about this, I said what I have to say,” Soumillon said after finishing third on the first of his five rides on Saturday’s card, having ignored calls – including one from a co-owner of Malavath, a horse he is due to ride here on Sunday – to stand down from his engagements over the most prestigious weekend of the European season.

Soumillon picked up a 60-day ban for Friday’s incident, from which Ryan emerged unscathed, but his suspension does not begin for a fortnight and it also emerged on Saturday that France Galop, the sport’s ruling body in the country, may change its rules to ensure that an immediate suspension is an option in future.

“From what we saw yesterday we would like to be in a position to impose a ban which starts immediately in those circumstances,” said Olivier Delloye, France Galop’s chief executive.

“It is very hard for people to understand after such an incident that the jockey can keep riding for 14 days.”

Friday’s incident slightly overshadowed the run-in to the Arc, for which runners trained in five countries – Ireland, Britain, France, Germany and Japan – filled the first five places in the betting after Thursday’s draw for stall positions.

The cosmopolitan field for the 101st running of European racing’s showpiece event is also one of the most closely matched of recent years, with Timeform’s ratings suggesting Titleholder, the shortest-priced of four challengers from Japan, is the best horse in the 20-strong field, but by only a whisker. Half the runners are within 5lb of Toru Kurita’s colt according to their calculations and only five have 7lb or more to find with him.

Twelve months after Torquator Tasso’s 80-1 success reduced much of the Longchamp crowd to astonished silence, this year’s race has the shape and feel of another with the potential for an upset.

Significant rain during the week has put a question mark against several fancied runners. It was mainly dry at Longchamp on Saturday but the closing stages of the Prix du Cadran, in which Kyprios drifted all the way across the track before securing an easy win, looked more like a three-mile chase at Hexham in January.

Titleholder and Soumillon’s mount, Vadeni, who will be moving up from 10 furlongs to a mile and a half for the first time on Sunday, are among those whose ability to act on testing ground is uncertain. Luxembourg, the narrow favourite after his win in the Irish Champion Stakes last month, has winning form on heavy ground but he, too, is moving into unknown territory at the trip and will be running for the third time since 13 August after suffering a muscular injury earlier in the season.

Torquator Tasso’s chance has improved with the rain but his wide draw in stall 18 is a significant obstacle, while Alpinista, who would be a hugely popular winner with the travelling British fans, is another whose ability to cope with deep ground is unproven.

The first name in the betting with no obvious concerns about the trip, going or draw, in fact, is Onesto, the Grand Prix de Paris winner, and he could well develop a head of steam in the market. Fabrice Chappet’s three-year-old was still available at 12-1 on Saturdayand that seems much too big for a colt who ran Luxembourg to half a length in the Irish Champion Stakes last time out.

Unlike Luxembourg, Onesto has Group One-winning form at 12 furlongs in the book, and over Sunday’s track and trip, too.

Uttoxeter: 1.08 Are U Wise To That, 1.43 Seigneur Des As, 2.18 Aucunrisque, 2.53 Encashment (nb), 3.28 Lucky Lover boy (nap), 4.03 Easkey Lad, 4.38 Butler’s Brief, 5.13 Jamacho

Kelso: 1.25 The Navigator, 2.00 Traprain Law, 2.35 Haute Estime, 3.12 Malystic, 3.45 Whelans Bridge, 4.20 Raddle And Hum, 4.55 Bestiarius

Anyone looking for a big outsider to back each-way, meanwhile, should give Japan’s Do Deuce careful thought at around 28-1. The Japanese Derby winner travelled noticeably well until tiring in the closing stages of the Prix Niel last month and should find plenty of improvement for his first start in over three months.