The third major challenger in Saturday's King George VI And Queen Elizabeth Stakes, as far as the betting is concerned, is Aidan O'Brien's much-vaunted St Nicholas Abbey.

Following a brilliant unbeaten juvenile year, his Classic season was a forgettable one, with his sixth-placed finish when a hot favourite for the 2000 Guineas proving to be his only racecourse appearance.

His first start of this year suggested he was past his best, but he has bounced back with victories at Chester and most recently in the Coronation Cup at Epsom.

Another huge story in the race is the jockey booking of O'Brien's son, Joseph.

With no official Ballydoyle stable jockey to call upon this season, O'Brien has varied his riding arrangements and 18-year-old O'Brien junior is thrilled to have come in for such a prestigious ride.

"I'm looking forward to the race. I haven't ridden him in a race before, but I ride him in a lot of his work at home," said O'Brien.

"It's a very, very good race and all I can do is ride my horse to the best of his ability.

"A big thanks go to the owners for giving me the opportunity to ride the horse and I'm really looking forward to it."