Clive Cox’s colt, a Group Two-winning juvenile before finishing second in last year’s Middle Park Stakes at Newmarket, marked his seasonal return at the top level with a length-and-a-half triumph in the feature race on day four.
Adam Kirby had the 5-1 victor handily placed behind the pace set by Mums Tipple, before pouncing in the final two furlongs to win with authority.
American filly Kimari, sent off at the same price as the winner, had to settle for second place for the second year in succession at the famous meeting – having finished runner-up for Wesley Ward in the Queen Mary Stakes 12 months ago.
Ventura Rebel stayed on into third at 50-1, two and a half lengths further back.
Cox said: "I'm very proud of him. He's a lovely big, strong horse. He was a wonderful two-year-old, but with the size and scope he had we were always hopeful that when he strengthened into his frame he'd improve again.
"To win a Group One first time out with any horse is very special. A Commonwealth Cup means an awful lot, so hopefully he can carry it on.
"I think he's ahead of where Lethal Force was in his career, I don't think there's any doubt. Lethal Force came into his own at four winning the Jubilee and the July Cup, but I think this fellow is in front of him at this stage.
"He's in the same box as his dad and Harry Angel was in it, too.
"He's really grown into his frame now. Last year he was very good and he's improved again. Adam knows him well enough now, one quality he has is a great cruising speed.
"I've lost my voice so I was probably more visible in the stands than most this week.
"The July Cup looks to be the next obvious step if he comes out of this well."
Kirby said: "He's a proper horse and he's done nothing but improve. He strengthened up very well over the winter.
"He's just like his dad, Lethal Force - he's improving as time goes on. He jumped away and travelled good and has got a very high cruising speed. He's just like his dad, apart from he's a different colour.
"He's very quick, but hits the line very strong over six furlongs. I can't see any reason why we would change it."
Asked how he compares to previous sprint stars he has ridden, including Lethal Force and Harry Angel, Kirby said: "He's quite a special horse.
"I've been lucky to ride a lot of very good sprinters and in my book, this lad is right up there. I think it would be a very brave statement to say he's the best I've ridden, but he's extremely talented."
Frankie Dettori said of Kimari: "It was a super run just the ground was a bit sticky. She came there to win, but she couldn't pick up."
Richard Fahey said of Ventura Rebel: "He was second in the Norfolk last year where he was a little bit unlucky, so he seems to like the place. He is a young horse that is still learning. He had a short season last season and I'd like to think he will go and progress again.
"He goes in any ground as he has form on both quick and soft ground. He did need it at Newcastle as he hadn't run since the Super Sprint at Newbury and I had been easy on him as well, as he had a little problem.
"We might go seven with him next time, but we will just see how he is."Last chance to get your free month trial of Racing TV! Every race live from over 80 meetings from some of the best British and Irish racecourses. Click here for more details.
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