John Gosden won the bet365 Classic Trial at Sandown on Friday, but it was the lesser-fancied Cunco who claimed the honours as hot favourite Monarchs Glen flopped.
The result continues Gosden's incredible recent run of form but backers of Monarchs Glen started to get worried when he began to get buzzed up pre-race.
Cunco (5-1), who was the first son of Frankel to win on a racecourse last year, was settled out the back by Robert Tart as Frankie Dettori tried to make all on his stablemate.
Dettori soon knew his fate as Frankuus and Intern breezed past, but it was Tart's mount who finished best of all, beating Intern by a head.
Tart said: "I ride him at home every morning, he's very quirky but he gets 10 furlongs well and he enjoyed the good to soft ground."
Gosden said: "I did say to Robert beforehand that his horse would love the ground.
"They didn't go quick but there's no doubt at all that he outstayed them.
"He ran great in France last time, finishing in front of Frankuus, so that form is solid.
"The other lad didn't look happy on the ground to me, having won on the all-weather, but it will be lovely ground for the jumpers tomorrow!
"Cunco had been working nicely at home and I told him to come late, it's a stiff hill and the one thing he has is plenty of stamina.
"I was thinking of going for the Chester Vase, which I may still do with a penalty - he's a tough little fellow. The other horse we'll just look for better ground."
Sir Michael Stoute's Ulysses made a pleasing return to action when running out a cosy winner of the bet365 Gordon Richards Stakes.
Last seen finishing fourth in the Breeders' Cup Turf, he looks the stereotypical older horse with which Stoute does so well.
Beautifully bred, by champion sire Galileo out of an Oaks winner in Light Shift, he was a Group Three winner last season but looks set to be a player in all the major prizes this season.
Ryan Moore tried to make all on Deauville and having fended off the challenge of Royal Artillery probably felt he would go on to win, but Andrea Atzeni cruised by under hands and heels to win by a length at 3-1, with 11-4 favourite My Dream Boat getting going too late in third.
Atzeni said: "He travelled nicely and settled which was the most important thing.
"The ground is pretty slow out there, but he wouldn't want it any slower than that. He picked up well when I wanted him to.
"He's a different horse this year, much stronger and mentally more mature, he's a horse with a bright future.
"I'd say 10 furlongs is his trip, but he hit the line quite strong."
Alan Cooper, racing manager to winning owners Flaxman Stables Ireland Ltd, said: "He did that very smoothly and he picked up gently to do it well.
"The thought at the moment is to stay at 10 furlongs rather than 12 and that is why he has entries in the Tattersalls Gold Cup and the Prince of Wales's Stakes.
"We'll see what Sir Michael would like to do, as he is the boss.
"The ground was a little bit slower than ideal, but he handled it well."
He added: "Let's get through May and June and then think about July (Eclipse), but he's a course and distance winner so why not think about it?"
Northern raiders dominated the bet365 Mile as Sovereign Debt held off the late thrust of Gabrial.
Having won on All-Weather Finals Day at Lingfield on just his second run for Ruth Carr, this was a stiffer task but the result barely looked in doubt.
Sent off the 9-2 joint-favourite, the winner sat just off the pace before James Sullivan kicked, taking two lengths out of the field a furlong out, and that proved decisive.
Richard Fahey's Gabrial lunged late but went down by half a length with the same back to Jallota.
The eight-year-old became the oldest winner in the race's history.
"Wasn't I lucky the day I got that phone call, my name just came up when David (Nicholls)) retired," said Carr.
"It's a big day for us, our first runner in a Group race and it's a winner.
"Jimmy kept the ride on him after Lingfield and it's a big day for all the team.
"He might be eight but he's not getting worse."
She added: "Plan A was Lingfield so where we go next I don't know, we had a choice of coming here or Leicester (King Richard III Stakes on Saturday) but there was twice as much prize money here and it wasn't a much harder race, so that's why we came."
Sullivan said: "I'm two for two at Sandown and two from two on him, he did it very well.
"He travelled, he loved the ground being a bit softer and did it well in the end.
"He showed a good attitude, I was in front a bit soon but he stuck on well."
Atty Persse underlined his star potential when overcoming trouble in running to maintain his unbeaten record with victory in the bet365 Esher Cup Handicap at Sandown.
With entries in both the Dante and the Derby, the three-year-old moved a step nearer to fulfilling those lofty engagements when running out a narrow winner of the mile prize.
After sustaining an early bump, the son of Frankel looked held approaching the final two furlongs having come under a drive from James Doyle, but as the gaps appeared late on the 6-4 favourite stuck his head out to get up on the line and score by a short head.
Winning trainer Roger Charlton said: "It was a tough race. I think for a little horse he got bashed round the bend and squeezed out.
"I thought a furlong and a half out his price had slipped to 20-1. He battled and did it well.
"I don't know where he will go yet. I will talk to John Ferguson and see what he wants to do, they (Godolphin) do not buy horses to run in handicaps. If we can step him up in grade something like the Dee Stakes might be a possibility."