Derby hero Workforce provided trainer Sir Michael Stoutewith his first ever winner in the Prix de l'Arc de Triomphe when he edged out Japanese raider Nakayama Festa in a thrilling finish to Sunday's showpiece race at Longchamp.

The colt, who looked in fantastic condition before the race, was given a brilliant ride by Ryan Moore, who was also securing his maiden victory in the prestigious contest. For owner-breeder Khalid Abdullah it was a fourth success following Rainbow Quest (1985), Dancing Brave (1986) and Rail Link (2006).

If the closing stages of the race were exciting, further drama followed as a stewards' inquiry was called into what looked a rough race. It did not affect Workforce and the Stoute team were able to celebrate their victory.

Stoute's previous best efforts in the Arc came courtesy of Pilsudski, who finished second in 1996 and 1997, and Workforce's win will surely rank as one of the Newmarket trainer's finest achievements.

Following his imperious seven-length triumph, in which he set a new track record in the Investec Derby, Workforce was sent off the 8-11 favourite to win the King George VI and Queen Elizabeth Stakes.

However, he failed to fire at Ascot, finishing 17 lengths behind stablemate Harbinger, who was himself denied a crack at the Arc following a career-ending injury suffered on the gallops.

"Workforce's come here on the back of a big disappointment," Stoute said. "It's been a big team effort and the jockey gave him some ride.

"If you have any ambition asa trainer when you start training you want to win the Arc. We've had lots of horses run well but I'm thrilled to have won it. He was so impressive in the Derby, but he ran inexplicably badly in the King George.

"Ryan was kicking himself after the King George and I was probably too hard on the horse before the race. He was right back to his best today and had a great battle with the Japanese horse."

Workforce's participation in the Arc had been in doubt until Thursday, when connections finally committed him to the race after he satisfied with his work, and as such it was a great training performance from Stoute to get him to the race in peak condition.

Given tremendous assistance by the ice-cool Moore, Workforce (SP 6-1, 8.6PMU) raced against the rail as Pouvoir Absolu attempted to set a decent gallop for her stablemate Planteur.

The Aidan O'Brien-trained Fame And Glory - sixth behind Sea The Stars in last year's race - was also handy, while Prix Niel winner and 9-2 Arc favourite Behkabad kept a close eye on the leaders.

Entering the straight, Workforce started to build momentum as the Aga Khan's Sarafina (12-1) had her progress checked by O'Brien's St Leger runner-up Midas Touch. She ran on gamely for third despite the interference, but the first two pulled well clear, with Workforce emerging on top by a head under an energetic Moore.

"He's back to his best," said the elated jockey.

"He's put up a nice run. It got a bit tight on the false bend. He quickened nicely and the Japanese horse kept him honest, but he just kept finding."

Yoshitaka Ninomiya, trainer of 22-1 shot Nakayama Festa, was exasperated.

Ninomiya trained El Condor Pasa to finish second in the 1999 Arc behind Montjeu and said: "Second again! Always second! He's a very tough horse, he will go back to Japan but there are no plans at the moment."

The Aga Khan, who also owns fourth-home Behkabad, said: "They should have been closer. Sarafina was interfered with and had to run outside, while Behkabad had nowhere to go."

The 19-runner contest was the subject of a lengthy stewards' inquiry that demoted seventh home Planteur to last, and O'Brien said of the fifth-placed Fame And Glory, who was hampered by Planteur half a furlong out: "It was a rough race and Fame And Glory was just about to challenge when Johnny [Murtagh] was nearly knocked off! That is what you call interference!"

Anthony Crastus, Planteur's jockey, was given a two-day ban forcareless riding, while William Buick also incurred the same punishment for that offence on the John Gosden-trained Duncan, who was 15th.

The Mick Channon-trained Youmzain, who had finished second in the last three Arcs - beaten less than five lengths in total - tracked Workforce, but never looked like improving his Arc record.

He was tenth and rider Richard Hughes said: "He was as dead as a dodo out there today."

A son of King's Best, who won the 2,000 Guineas in 2000, Worforce raced once as a juvenile, winning a Goodwood maiden by six lengths.

He was not seen again that year as ante-post punters deliberated whether he would try to emulate his sire at Newmarket or head to Epsom.

The Derby was indeed the plan, but Workforce's preparation suffered a blow when he was beaten by Cape Blanco, who finished 13th in the Arc, in the Totesport Dante Stakes.

Connections were not toodismayed, though, and Epsom remained the target, although Moore was forced to wear the Abdullah second colours as Tom Queally sported the famous pink cap aboard the Henry Cecil-trained Lingfield Derby Trial winner Bullet Train.

However, Workforce proved himself a top-class colt with an awesome performance at Epsom and sealed his place in racing folklore by becoming the sixth horse to the land the Derby-Arc double.

He could yet add to his 2010 achievements by staying in training next season.

Teddy Grimthorpe, Abdullah's racing manager, said of that exciting prospect: "It's always a good thing for racing for a Derby and Arc winner to stay in training but the horse will be the primary decider."