Sire De Grugy completed a hat-trick of notable victories with a convincing victory in the Sodexo Clarence House Chase at Ascot.
The Tingle Creek and Desert Orchid Chase winner looked different class in the closing stages as he stormed past Irish runner Hidden Cyclone over the last two fences.
Sire De Grugy (5-4 favourite), trained by Gary Moore and ridden by his son, Jamie, galloped home by 11 lengths.
There was no emotional triumph for Somersby as the 2012 winner unseated Dominic Elsworth with the race barely at halfway.
Jamie Moore said: "This is all about the horse - some of the jumps he put in were spectacular.
"He was magic today, all the credit to the horse.
"Today he felt as good as he has ever felt.
"Sprinter Sacre is a great horse, but today was his most impressive performance.
"I'm not saying he'll beat the other horse (Sprinter Sacre), but he could do."
The winning trainer said: "He has got his quirks because he's French.
"When he first came to us he was a very free horse. Jamie's done a great job and settled him now.
"He has a cross noseband on because he's quirky. We could probably do away with that now but we won't.
"He's settled down lovely and he switched off great. His great asset is his jumping.
"I don't think the ground is as heavy as people thought. They've gone a good gallop and made it a true-run race. Fair play to the horse.
"This is only his second season as a chaser, at the end of the day. He was a novice last year.
"He's got to go for the Champion Chase. I think he's an improving horse and I've got nearly two months to freshen him up.
"I'll give him a nice break for a couple of weeks then we'll bring him back purposely for the Champion Chase. He deserves to be in it."
Hidden Cyclone's trainer Shark Hanlon was delighted with the performance of his raider.
He said: "He was beaten by a very good horse. We thought he wanted softer ground, but Andrew (McNamara, jockey) felt he jumped better on better ground.
"He's better going the other way and it's more than likely that he'll go for the Queen Mother."
Elsworth said of Somersby: "He just got a bit close to the fence, screwed it, and then slithered on landing at one of the downhill fences. It was one of those things.
"I'm OK and the horse is OK so we live to go another day."