It wasn't the scenario Aidan O'Brien had envisaged on the eve of another Breeders' Cup Saturday.

Then, giving his final thoughts before the curtain was raised on the 24th championships, he looked ahead to the Classic, in which the iconic George Washington was to make his swansong.

"George is the exciting one," he said. "When you know George, you can believe anything can happen."

That notion was still very much alive shortly after 5.30pm on the apron at the edge of the Monmouth Park main track, where O'Brien, his wife Anne-Marie and their four children stood engaged in idle conversation withJohnny Murtagh and his wife Orla.

The results from four races in which the O'Brien team had been involved so far were mixed. Achill Island had finished second in the Juvenile Turf the previous day, All My Loving run a creditable fifth in the Filly & Mare Turf, Excellent Art snatched a gallant second from a hopeless draw but Dylan Thomas, hot favourite for the Turf, had floundered.

It was time for the last Cup event. There were no lofty expectations, but if George Washington, Ballydoyle stable's signature horse for the past three seasons, could produce another positive performance on the dirt, the O'Brien family could leave Monmouth and head home.

At 5.47pm the mood altered significantly. The pictures on the giant screen on the infield had shown George Washington leaving the stalls on terms and turn into the first bend in contention and holding fifth place.

He began to labour at the end of the backstretch and when he reached the straight, Mick Kinane had eased up on him. Their race was over and they dropped out of the camera shot.

Curlin flashed past the line, a stunning four and a half length winner of a $5million race to widespread glee followed by seven others. One of the runners was missing.

The O'Briens peered down the track where, 100 yards away, George Washington had been brought to a stop in front of the grandstand, the victim of a catastrophic leg injury. People were running to his aid, the screens were being erected. We all knew what would follow.

O'Brien stayedwhere he was for a few minutes, his wife was blinking away tears. Orla Murtagh offered a consoling shoulder. Then he instructed them to wait while he went onto the track. The visit was brief. He returned to collect his family and began to leave.

Attempts to get a reaction from O'Brien yielded no response. By now in tears himself, this was a time when the heart-broken trainer, so patient with the media throughout the week, would keep his thoughts to himself.

Behind him were John and Sue Magnier, George Washington's owners. John Magnier commiserated with the Ballydoyle stable staff, giving a hug and a pat to each one, all distraught at the loss of the universally popular 'Gorgeous George'.

O'Brien reached an area near the jockeys' room where he stopped to make a phone call and then spoke with a comforting face from back home, fellow trainer John Oxx, while in the adjacent press conference room Dr C Wayne McIlwraith confirmed the worst. George Washington had been euthanised at O'Brien's request. The injury was "hopeless".

Then the O'Briens walked out of Monmouth Park, almost certainly never to return.

GEORGE WASHINGTON'S Breeders' Cup Classic bid ended in tragedy as he suffered a fatal injury in a race won in brilliant fashion by Curlin at Monmouth Park.

The Aidan O'Brien-trained four-year-old showed up handily early in the $5million contest, which was run on mud-splattereddirt track, but soon began to struggle.

As Curlin powered away to beat Hard Spun, George Washington's rider Mick Kinane dismounted his horse, who was quickly attended by racecourse veterinary staff.

He could not be saved, however, and the decision was taken to have him humanely destroyed.

O'Brien's wife Anne-Marie was in floods of tears on the rail and was then consoled by her husband as the family walked back into the paddock.

On-course veterinarian and equine joint expert Dr Wayne McIlwraith said George Washington suffered an open fracture of both sesamoid bones.

Dr McIlwraith added: "The decision was made very quickly. The injury was bad and Aidan O'Brien made the request for euthanisation. He was with the horse."

George Washingtonwas never far from the headlines throughout his mercurial career.

An emphatic winner of last year's 2,000 Guineas, he was then beaten by Araafa in the Irish equivalent in heavy ground.

However, O'Brien used all his skills to return the son of Danehill to his very best and he gained his revenge on his Irish Guineas conqueror in the Queen Elizabeth II Stakes at Ascot - a race which saw him crowned as the champion three-year-old miler.

He was then sent off to stud and was obviously a very popular proposition for breeders, but it was discovered very early that he was only managing to get a small percentage of his mares in foal.

He was sensationally returned to training, a move which saw leading Classic prospect Holy Roman Emperor retired early to take his place in the breeding sheds.

It is fair to say that George Washington has only shown flashes of his brilliance this season, but still offered enough to suggest he had retained plenty of ability.

He was not beaten far in the Queen Anne at Royal Ascot, the Coral-Eclipse at Sandown and Prix du Moulin at Longchamp and always sparked excitement and interest wherever he ran.

AIDAN O'Brien acknowledged on Monday that he and his staff at Ballydoyle face a big task with mercurial Group 1 winner George Washington on his return to training after a less-than-successful start to his career as a stallion.

O'Brien, who handled George Washington with great skill to win four Group 1 races before his retirement, said: "We will have to work at once again getting George's mind unravelled.

“I'm told he has got six mares in foal and it is possible that things could go right for him at stud next year, but for now we're planning to bring back to the track depending on how things go with him.

"Since he came back here from Coolmore he's been like a horse with five legs and we have to get him thinking that he can't cover everything he sees.

"He's in an isolation yard here and I'd imagine we will start re-introducing him to other horses by degrees over the next week or two. “We have a lake here, which we use at times, and he wasled down and ridden into it a few days ago. He swam across it, so you can't question his courage."

Regarding possible targets, O'Brien said: "It's far too early to say where he might start off, but the Tattersalls Gold Cup is probably going to come abit too soon for him and, if all goes well with him, it will probably be Royal Ascot before he runs.

“If everything goes to plan he will probably start back in the Queen Anne Stakes.

"He is a horse who was immature mentally as a two-year-old and again early last season, but his attitude improved all through last year.

"Because his mind has been on other things recently, it is going to be a day by day job to get him concentrating on being a racehorse again and we will just have to wait and seehow things go."