What are the clues that can help us spot a Derby outsider who might actually win?

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City Of Troy's flop on Saturday did more than allow a shock outcome to the 2,000 Guineas. It also blew the Betfred Derby picture wide open. 

He'd been 6-4 for Epsom until that thoroughly disappointing reappearance. You can now get 7-1, though he seems to be attracting a bit of interest at that price. It wouldn't do for me. 

As I may have said before, I prefer somewhat bigger odds and, gratifyingly, the Derby has been won by four horses at double-figure odds in the past seven years. Unfortunately, I didn't back any of them. 

Still, I'm keen to understand why those Derby heroes were returned at generous SPs. If we crack that puzzle, we may see the next shock result coming - possibly as soon as next month. 

So who were they? 

Wings Of Eagles 40-1

If you backed him, please email to gloat about it and explain your thinking. Who wouldn't want to back a Derby winner at Grand National odds? 

He arrived at Epsom as the winner of just one of his five races, a Killarney maiden the previous August. Strong form, it was not. Still, there was enough there for our analyst, Justin O'Hanlon, to say: "The winner may still be very green. If he was, he could be fairly useful." 

To judge by his Racing Post Rating, he showed gradual progress in two more juvenile runs but I feel fairly confident in asserting he was not the type to be highlighted as a Derby winner in waiting by any of those clever pundits who publish season preview annuals every March. There just wasn't enough promise. The main lesson of Wings Of Eagles is that low-level juvenile form doesn't stop you flourishing at three. 

Wings Of Eagles and Padraig Beggy following their 2017 Derby winCredit: Mark Cranham

He reappeared in the Chester Vase as the least fancied of three Aidan O'Brien runners and, after being held up, finished quite nicely into second place behind Venice Beach, the favourite. "Disorganised over 1f out," says the close-up comment, a rare outing for the D-word but entirely fair, as Wings Of Eagles seemed not to know what to do with his legs off the final bend. 

He was growing up but it still wasn't the most promising effort, bearing in mind Epsom's unique demands. I don't suppose anyone at Ballydoyle really fancied him. But perhaps they thought, we'll send him over, he can hack around at the back and pick up the pieces. 

Which turned out to be exactly the right tactics for a strongly-run Derby. If he'd been fancied, there'd have been pressure to get him closer to the pace and that might have stopped him winning. 

Serpentine 25-1

This was the Derby behind closed doors in the Covid year of 2020 and perhaps the lack of atmosphere meant some of the jockeys weren't as much on their game as they normally would be. Anyway, Serpentine was the pacemaker and they completely let him go. 

In fact, riders on the fancied horses misread the pace so badly, they couldn't even reel in the two other outsiders who'd been in second and third from an early stage. 

It was a ridiculous race and you wouldn't want to try learning many lessons from it, due to the unique circumstances. This Derby, after all, was staged in July. Serpentine had won his maiden the previous weekend, racing having only recently resumed from the Covid break. 

Serpentine is out in splendid isolation inside the final furlong of the DerbyCredit: Edward Whitaker

It took him almost four years to win another race, at Rosehill two months ago. Stuff like this isn't going to happen again - if we're lucky. 

That said, pacemakers can sometimes win if they're gifted a soft lead. Maroof and Summoner in the QEII, Sovereign in the Irish Derby... it happens, though not very often. It's something to keep in mind when thinking about how a race might be run. If there's just one pacemaker and no one thinks he's a threat, that makes him a threat. 

Adayar 16-1

A year after Serpentine came this Godolphin winner. They had this in common: just one win before Epsom, by a wide margin in a maiden. 

For Adayar, that had been in the Nottingham mud in the late October of his juvenile season. It was enough by itself to make him a Derby contender in some eyes. 

But on the big day he was available at 40-1 until minutes before the 'off', with only a late plunge on the Betfair exchange shortening him to 16s. A big part of the reason was his two defeats in Derby trials that spring. 

Adayar storms to Derby glory under Adam KirbyCredit: Edward Whitaker

Excuses could be made and, as it turns out, they were valid. He was held up, racing too keenly, on his reappearance in Sandown's Classic Trial, a race in which the other principals were handy from the outset. He did well to make up so much ground and we ought to have seen the possibilities in his ground-devouring stride. 

Soft ground wasn't for him in Lingfield's Derby Trial a fortnight later. Even so, he was strong at the line in second place. 

He seemed to be Charlie Appleby's third string in the Derby, which helped inflate his odds. Most punters hate to back a horse who has a more fancied stablemate but Appleby and O'Brien have such strength in depth that they can win top-class races with their back-up runners. Such horses are always worth a second look. 

Masar 16-1

He wouldn't be 16-1 if that race happened now. This was 2018, before Appleby became the force he is now. The trainer had won a modest handful of Group 1s but no Classics. 

O'Brien was reckoned to be a much more likely source of Derby winners and his Saxon Warrior, the Guineas winner, was sent off at 4-5. But Masar had less than two lengths to make up on that Newmarket form and his pedigree (with Urban Sea on both sides) suggested he would really appreciate the extra half-mile. 

Masar (William Buick) wins from Dee Ex Bee in the 2018 DerbyCredit: Mark Cranham

It certainly looks like stamina was important that day at Epsom, with subsequent Cup horse Dee Ex Bee in second. Poor Roaring Lion didn't quite see out the trip in finishing a game third. 

What does it all mean?

A Guineas, a Chester Vase, Sandown, Lingfield, a Curragh maiden ... there's no common route to Epsom for these winning outsiders and there's no reason why there should be. 

What they have in common is that they came from immensely powerful stables. They were well bred and sifted out from a large number of potential candidates; they just hadn't got around to showing the full extent of their ability on the track. Three of them had more fancied stablemates, which, in my mind, is the main reason they were underestimated. 

So the Derby is not a race in which to side with the best horse from a small yard. Very few trainers are given the right sort of raw material. O'Brien and Appleby have, between them, won this Classic six times in the last seven years. 

Already, they dominate betting on next month's race. Arabian Crown (Appleby) and Henry Longfellow and City Of Troy (both O'Brien) are the obvious ones. The game, this trial season, is to spot what else they might run that's sailing below most radars.

Read these next:

What's on this week: Chester's May meeting and Lingfield Classic trials provide Epsom clues before Sunday's French Guineas

City Of Troy bred to stay so it's too early to write him off at 8-1 for Derby - three things we learned this week  

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The Front Runner is our unmissable email newsletter available exclusively to Members' Club Ultimate subscribers. Chris Cook, the reigning Racing Writer of the Year, provides his take on the day's biggest stories and tips for the upcoming racing every morning from Monday to Friday. Not a Members' Club Ultimate subscriber? Click here to join today and also receive our Ultimate Daily emails plus our full range of fantastic website and newspaper content.