Question marks over the extended mile and six furlong trip and fast ground were answered in style as Kingston Hill powered to victory under regular rider Andrea Atzeni.
Andrea settled Kingston Hill towards the rear. He relaxed well and was soon in a good rhythm.
On entering the straight, Kingston Hill had just two horses behind him but the ever-cool Andrea didn’t panic and switched to the outside to make his run.
The race was unfolding towards the far rail with Forever Now and Hartnell locking horns with three furlongs to run.
The Derby third Romsdal came to take over the running under William Buick but Kingston was just hitting full stride and Andrea produced him inside the final furlong to challenge for the lead.
He drifted towards the far rail but was soon in command, passing the post a length and a quarter to the good.
Roger said: “I can't put it into words. It's brilliant, it's a relief and exciting. It's an exciting thing to win a Classic and it's what we're all in it for.
“It's great for the horse. We've had a bit of heartache with him through the year. He came good on the day and Andrea gave him a brilliant ride.
“The plan was always to come with a long run down the outside as he's not a horse who quickens instantly.
“He's got a big, long stride and a long straight like this is ideal. I was a bit worried three out as I thought we might have a bit too much ground to cover, but he's stayed on well and shown his class.
“I'm delighted for the horse to win a Group One this year. He looked a Classic horse at the start of the year and he's won a Classic.”
Andrea added: “I don't know what to say, it's a dream really. It's unbelievable.
“I rode him like the best horse in the race, he travelled beautifully. He's so laid-back, he goes to sleep.
“When I pulled him out he was always going to get there. He was just wandering about when he hit the front.”