With Godolphin leaning heavily toward running Irish Champion Stakes winner Grandera in Australia's Cox Plate on Oct. 26, there is a good chance that regular rider Frankie Dettori will be assigned the mount, costing him a chance to compete in this year's Breeders' Cup World Thoroughbred Championships.Grandera is the current leader in the World Series championship, which Godolphin has won with Daylami and Fantastic Light twice.Dettori, who has won the Breeders' Cup Turf twice and the Breeders' Cup Mile, said he believes if Grandera does journey to Australia, he will be the rider."There's a long way to go yet," Dettori said in the Racing Post, "but right now it looks as if Grandera will run in the Cox Plate, and I'm sure Godolphin will want me to go down there, because I get along so well with him. The Cox Plate is a big, big race, which we have never won. And I don't think Godolphin would want anyone else on Grandera but me. After all, he's our number one horse."In addition to the Irish Champion Stakes, Grandera has also captured the Singapore Cup and Prince of Wales's Stakes at Royal Ascot this year.Godolphin manager Simon Crisford, however, said no decision has been made whether Dettori would ride in the Cox Plate or World Thoroughbred Championships. "Whatever we decide, it's not a sign that we're downplaying the importance of the Breeders' Cup," he said. "It's possible that Frankie will ride in the Cox Plate. Equally, he could be in Chicago for the Breeders' Cup."Godolphin's decision could hinge on how well Sakhee runs in his next start and whether last year's Arc de Triomphe winner and Breeders' Cup Classic runner-up looks to be a strong force for the World Thoroughbred Championships.