Aidan O'Brien feels George Washington is ready for the dirt at Churchill Downs

"It's a big gamble running George Washington in the Classic but he is so different to any horse we have had ability-wise," he told Ceefax Racing.

"We are hoping that his ability can overcome everything else he will face on the dirt at Churchill Downs.

"We will never know what will happen unless we give it a try."

O'Brien feels that George Washington is fully prepared for his day in the spotlight in the US$5m classic in Kentucky.

"It wasn't too much of a hindrance when he missed a gallop at Southwell as he didn't lose too much work-wise," explained the Ballydoyle handler.

"We were simply hoping he could get some experience of the kickback and it was just another piece in the jigsaw.

"He has behaved well on his last couple of runs and has grown up mentally."

O'Brien has three chances in the Breeders' Cup Mile - Aussie Rules, Ad Valorem and Ivan Denisovich.

"Aussie Rules is a well-balanced type and won well in Keeneland, which was a nice prep race. He has recovered well and we are happy with him," he said.

"Ad Valorem ran well last time in Canada and his wins in the Middle Park and Queen Anne shows he has the class.

"Ivan Denisovich gets a mile well, but he won't be wearing the visor this time as he ran a bit keen in it at Ascot."

Scorpion goes for O'Brien in the $3m the Breeders' Cup Turf on Saturday in only his second start of 2006.

"He fractured a pastern in the spring this year and lost lots of time in the summer, but he has made really good progress," said O'Brien.

"We were very pleased with his run at the Curragh (Barathea Finale Stakes) and I felt he ran a nice race.