RACING: Aidan O'Brien yesterday welcomed the wet and cold weather as he made his first visit to Arlington racecourse, venue for tomorrow's Breeders' Cup.

But O'Brien, who arrived in the US late on Wednesday, warned that the effects of a long hard season could catch up with some of his powerful string.

O'Brien said that horses such as Rock of Gibraltar and Hawk Wing might now have done enough for the year.

But he did acknowledge that it was preferable to have bought them out to a venue where the weather is largely cold and unwelcoming rather than throwing them back into a warm environment.

O'Brien walked the turf course yesterday with Coolmore chief Demi O'Byrne and said: "It's good fast ground but there is absolutely no jar. If it carries on raining it will be on the slow side of good this Saturday."

He explained the decision to run Rock of Gibraltar in the Breeders' Cup Mile on the turf rather than his alternative engagement in the Classic.

"He's run over a mile all season and we just thought it might be a little unfair after a long season to go into the total unknown with him," O'Brien said.

"He cruises well, he kicks well, he is an exceptional horse. His coat has turned so we are just hoping a bit.

"Both Rock of Gibraltar and Landseer are drawn wide and they will need a lot of luck but they are both very good horses - I wouldn't be that surprised if Landseer was to beat Rock of Gibraltar.

"I imagine they will both be dropped back and then whichever gets the luck will go close."

O'Brien then turned his attention to the other horses he is running at the meeting, reluctantly nominating High Chaparral as his leading fancy.

"The plan was always to give him a prep, then go for the Arc and then Breeders' Cup," O'Brien said.

"He was very sick and missed his prep and then he just wasn't quite sharp enough in the Arc.

"He had a good blow afterwards but he didn't lose much weight and he has sharpened up well in his work since. He has come forward mentally.

"Hawk Wing has done nothing wrong all year and never really got his fast ground. He will need to be at his best but we have always said that he will handle the dirt.

"He's a huge, big horse and if he's coming to the end, you'll have to forgive him for it. But there is every possibility that he and High Chaparral will stay in training next year.

"In the Juvenile, Mick had the choice and chose Tomahawk. But he is a team player and he knows that whatever wins the chances are he will be on it next time.

"He is the one that really should act on the dirt. He is a lovely level mover and his pedigree is full of dirt horses. It is very much a question of how he took the Dewhurst.

"Van Nistelrooy has raced plenty to give him experience and he always shaped like he would stay this far. He likes to sit just behind the pace.

"Hold That Tiger won with Kieren Fallon on in France. I would imagine he will be dropped out and then Kieren will ride the race as he finds it.

"All of my horses have travelled well and seem very well. After they were sick in the middle of the season I thought we would have no horses here.

"But this is the Olympics of thoroughbred racing and I will be over the moon if we have just one winner."

Bob Baffert insisted yesterday that Kentucky Derby and Preakness Stakes winner War Emblem should not be deserted in Saturday's Breeders' Cup Classic.

The three-year-old arrived from Califronia on Wednesday and yesterday underwent a trip to the starting stalls as Baffert attempts to iron out his recent kink of starting slowly.

"We stood him in the gate because we wanted to make sure all was right and you never want to mess with the man with the button," Baffert said.

"War Emblem is a fast horse. I don't think Medaglia d'Oro can keep up with him.

"It's very natural that when a horse runs a bad race people start to jump off - it's like 'What have you done for me lately?'

" I feel that this horse is training well and he's ready to run well. He's a fast horse who likes to lead because it's his running style."

British trio Gossamer, Golan and Islington continued their build-ups by working on the turf course yesterday.