Proschema can upset O'Brien's Chester raiders
At even money, the market believes the quest to find this year's English Derby winner ended when Saxon Warrior won the 2,000 Guineas at Newmarket last Saturday - well before the eight days of trials, which take place at Chester, Lingfield, Leopardstown and York, began.
But it is never quite so straightforward and even Ballydoyle do not always have a handle on the pecking order of their middle-distance horses at this time of year.
Last year, Ballydoyle's number one going into Epsom was the Dee Stakes winner Cliffs Of Moher, but 40/1 shot Wings Of Eagles, which sailed down the outside to collar Ryan Moore's mount late on, was second in the MBNA Chester Vase a year ago.
O'Brien, who has won the Vase for the past five years, runs three today: Flag Of Honour, third in a French trial on heavy ground, Family Tree, a Gowran maiden winner, and Hunting Horn, third behind Sevenna Star and Ispolini, which he meets again, at Sandown Park. However, this does not seem like O'Brien's first XI and he may have to take a back seat.
The William Haggas-trained Young Rascal caught the eye winning a maiden at Newbury, but few races would give local trainer Tom Dascombe as much pleasure as a Chester Vase and it may be worth taking a chance on his Proschema, an 11-length winner at Haydock last time out.
"It's a job to know what he beat, but he did it well," said Dascombe. "He's not got a great draw, but we'll find out what we've got. We don't have many that get a trip, but he's definitely a Group horse - it's just a question of which Group."
One likely contender for the blue riband at Epsom is Study Of Man which will be considered for the race and the Prix du Jockey Club at Chantilly following an impressive display in the Prix Greffulhe at Saint-Cloud yesterday.
The son of Japanese superstar Deep Impact had to make do with the runner-up spot behind Martyn Meade's British challenger Chilean on his return to action in last month's Prix la Force at Longchamp.
Pascal Bary's charge was a hot favourite to return to winning ways in this 10-furlong Group Two and displayed an impressive change of gear in the hands of Stephane Pasquier to leave his rivals trailing in his wake.
O'Brien, meanwhile, is hoping Magic Wand can shed her maiden tag in today's Cheshire Oaks. The Ballydoyle handler has saddled five of the last 10 winners of the Listed contest and again launches a three-pronged assault. Ryan Moore has sided with Magic Wand, a half-sister to the 2013 Irish Oaks heroine Chicquita.
"Magic Wand is a lovely filly and a sister to Chicquita," O'Brien said. "She's had one run on bad ground this year and got a little bit tired.
Donnacha O'Brien partners another maiden in Forever Together, while Seamie Heffernan takes the ride on Dramatically, which won at Naas last year and steps up in trip after finishing down the field in the Nell Gwyn at Newmarket.
In Australia, the milk-shaking conspiracy, which involved five trainers, three stablehands and 123 races over seven years, has been described as the "biggest scandal in Australian horse-racing history".
The eight have been found guilty of giving illegal race-day treatments of sodium bicarbonate, mainly because of incriminating texts about "top ups" found on the phone of box driver Greg Nelligan after he was caught red-handed doping a runner last October.
The main trainer implicated in the conspiracy, Robert Smerdon, handed in his licence in March and did not participate in the inquiry. Penalties are expected to be handed down tomorrow.
Meanwhile, jockey Martin Ferris has announced his retirement on medical advice from his surgeon.
The Corkman suffered a severe leg break after a fall from Another Rebel in Galway at the end of October 2016.