Racing: Theatre in the Arc light: Sue Montgomery assesses the field for this afternoon's big race at Longchamp

THE Prix de l'Arc de Triomphe is probably the hardest race in Europe to win. It is always competitive, invariably rough, and the layout of Longchamp makes the course difficult and deceptive to ride. The horses are coming to the end of their season, the prize is large, and the jockeys will go for broke. This is not a trial for anything.

Some true champions set the seal on their greatness in the Arc - horses such as Corrida, Coronation, Ribot, Sea- Bird, Vaguely Noble, Mill Reef, Dancing Brave - but there have been some ordinary winners too. In the absence of any obvious superstars this afternoon's race does not look like a vintage contest, but it will be no less competitive for that.

The mile-and-a-half course at Longchamp is a fair test in that there are no extreme undulations, tight turns or odd cambers. But for the rider, there are plenty of traps for the unwary or inexperienced on the way to winning the pounds 457,666 first prize. Pat Eddery, one of a select band who have ridden four Arc winners, is on Intrepidity this afternoon and said: 'What you do need above all is luck. There are so many places where so many things can go wrong.'

The runners line up with their backs to the famous windmill and gallop straight and slightly uphill for about four furlongs. The problems can start as the field begins to swing from the top of the hill into the right-handed curve at the furthest point from the stands. Eddery adds: 'There is always a strong pace, you're running downhill, and horses are beginning to drop back as others make their move.'

As the gradient levels off, the bend into the straight unwinds deceptively, not once, but twice. The first turn, alongside the trees, is an illusion. The final three-furlong run to the finish actually begins once the runners clear the Bois on their left. To make matters worse there are two winning posts in sight, with the nearer one used for the Arc.

French-based Cash Asmussen, on Hernando today and at his best round Longchamp, warns: 'That first, false straight is such a temptation. But a jockey must never ask his horse for an effort there, or he'll crack half-way up the run-in. The word is patience. You must wait until you get into the straight proper before you make your final move.'

Unusually, a trio of British- trained horses are the first three in the ante-post betting lists. White Muzzle and Only Royale, second and fifth last year, are vying for favouritism, followed by King's Theatre, with Intrepidity and Carnegie the best-backed of the home side. But the French are desperately difficult to beat on their own, familiar turf. Their horses tend to have a break in mid-summer, and come to the Arc refreshed.

Andre Fabre had a field day when the traditional trials were run on the course three weeks ago, sending out the first three home in two of the races. He runs five today: Carnegie, winner of the Niel; Richard of York, Intrepidity and Apple Tree; plus the tough filly Bright Moon, who chased home White Muzzle in the Grand Prix de Deauville.

Three-year-olds and older horses have enjoyed similar levels of success in the Arc since the war. The English Classic form is represented by King's Theatre, second in two Derbies and winner of the King George, and the French by Celtic Arms, winner of the Prix du Jockey- Club. The colt, who has a devastating turn of foot from off the pace, ran fourth to Carnegie in the Niel and will be fitter today.

Racing started at Longchamp, set in a loop of the River Seine just two miles from the centre of Paris, in 1857. The Arc is not so old; it was first run in 1920, founded to revive racing after the First World War. In one memorable incident during the occupation of Paris in the Second World War Allied bombs intended for a nearby industrial area landed on the course during a meeting. Some punters were killed and the Tote was put out of action, but the track was hastily repaired and the races run.

A friendlier British presence attends Longchamp now. The annual invasion of racing fans have their own grandstand - the Pavilion Anglais - and though they may find the interminable queues at the betting windows hard to bear, the strains of Vivaldi played over the Tannoy between races must surely soothe a savage punter's breast.

The international rivalry - five countries will be represented by the 20 runners today - makes for a tremendous atmosphere, with each side cheering its own horses. One, Much Better, has made the long journey from Brazil, there is Lando from Germany, Big Tobin from Italy, and Millkom, unbeaten in 10 races, has come up from Pau, near the Pyrenees, to take on the Parisians. There are five horses from Britain: King's Theatre, Ezzoud, Only Royale (who will be trying to become the first British-trained mare to win the race), Broadway Flyer and White Muzzle.

Sheikh Mohammed has never won an Arc, but may have the key today with four runners, all with valid claims. Tough, handy King's Theatre, trained by Henry Cecil and ridden by Michael Kinane, can send the away fans home happy for the first time since the Irishman scored in 1989 on another Newmarket horse, Carroll House. The dangers from the home side are fast-improving Carnegie, whose mother Detroit won in 1980, Celtic Arms, and Millkom, who was foaled in Northamptonshire, sold for just 15,500 guineas, and whose breeder, the farmer Robert Percival, now follows his pride and joy all over France.

(Photograph omitted)