Dawn Approach leads a field of 13 declared for the Qipco 2000 Guineas at Newmarket on Saturday.
The Jim Bolger-trained colt, who has been drawn in stall six, will be defending a six-race unbeaten record in the colts' Classic, having rounded off his juvenile campaign with victory in the Dewhurst in October.
He will be joined by stablemate Leitir Mor, who was second in the Dewhurst.
Chief market opposition comes in the shape of Richard Hannon's Toronado, also unbeaten and most impressive in winning the Craven Stakes on his reappearance. He has been allotted stall 12.
Like Bolger, Hannon has a second string to his bow in the shape of Racing Post Trophy runner-up Van Der Neer.
Strong ante-post support in recent days has been for the Richard Fahey-trained Free Handicap victor Garswood and he also features, as does the Aidan O'Brien trio of Cristoforo Colombo, who will sport cheekpieces in the hands of Joseph O'Brien, Mars (Seamie Heffernan) and George Vancouver (Colm O'Donoghue).
Newmarket-based Italian Marco Botti is represented by Moohaajim, a crack juvenile who ran creditably when third on his return in the Greenham Stakes at Newbury.
Brian Meehan's Correspondent will be ridden by Paul Hanagan, while Henry Cecil runs the maiden Kyllachy Rise, the mount of Tom Queally, and Kevin Ryan calls on Glory Awaits.
The field is completed by a sixth Irish challenger in Niall Moran's Dont Bother Me.
Assessing ground conditions, which are described as good to firm, good in places, clerk of the course Michael Prosser told www.racinguk.com: "The track walks extremely even and I am very happy with that.
"We will stick with putting the stalls in the middle for the Guineas.
"The 2000 Guineas has a cracking feel to it, but there is real depth there too."
Coral make Dawn Approach the 11-8 favourite following the final declaration stage, ahead of the well-backed Toronado at 9-4.
Spokesman David Stevens said: "The betting is dominated by Dawn Approach and Toronado, suggesting it will be a major surprise if the race is not won by one of that duo, while Joseph O'Brien's decision to ride Cristoforo Colombo has seen that colt leapfrog his stablemate Mars in the market."