Harrison will have his stamina put to the test when he takes a step up in trip and class in the Ascot Gold Cup.

Although the four-year-old has yet to race beyond a mile and three-quarters, trainer Mick Channon expects the marathon two-and-a-half-mile trip to suit the Tim Radford-owned gelding, who won on his return to action at Chelmsford.

Harrison finished third in the King George V Stakes at the Royal meeting 12 months ago , and warmed up for a tilt at the Gold Cup when fourth in a Listed contest at York late last month.

Channon said: "Harrison will go for the Ascot Gold Cup.

"We all think he will stay, from Graham Lee right the way through the team.

"We've always thought he would be the sort of horse for this and it has always been on the back of our mind.

"All he does is stay and I don't think it (trip) will be a problem. They will go a decent pace all the way through and he has got that bit of class.

"Graham was upset with himself at York. We were pleased enough with the horse as he did everything right, Graham just beat himself up as he felt he went too early, but that happens in horse racing.

"He was probably the second-best horse in that race but finished fourth."

Channon hopes the weather will stay dry to allow Opal Tiara the best possible chance of being able to go one better than her most recent start in a Group Two at the Curragh when she tackles the Duke of Cambridge Stakes.

He said: "She ran well in Ireland, but the weather came against her.

"We were very pleased with her and she will go for the Duke of Cambridge now.

"She has been great and did well in Dubai over the winter. She is not showing any signs of being tired.

"She is as tough as old boots."