Saturday's Group 1 Derby has nine runners headed by the unbeaten Camelot, after his trainer Aidan O'Brien decided to rely on the hot favorite and Astrology.
Ireland's champion handler decided to take out three others -- Imperial Monarch, who will run instead in Sunday's Group 1 Prix du Jockey Club (French Derby); Father of Science; and Tower Rock. As a result, O'Brien will have his smallest number of Derby runners since 2004 when he had one participant.
O'Brien has won the premier colts' classic twice, in 2001 when Galileo was his only runner and the following year when High Chaparral was one of three to take part from Ballydoyle.
The 12-furlong classic, the richest race in Britain with £1,325,00 in prize money, is run for the 233rd time at Epsom Downs.
Camelot is unbeaten in three starts and comes into the Derby on the back of victory in the opening classic of the season, the Group 1 Two Thousand Guineas over a mile at Newmarket on May 5.
If successful, Camelot would become the 37th horse to win both classics and the first since Sea the Stars in 2009.
The son of Montjeu is 4-7 favorite with William Hill, the official betting partner of the 2012 Derby Festival. The last horse to win the Derby at odds-on was Shergar, who scored by a record 10 lengths when successful at 10-11 in 1981. Three odds-on favorites since -- El Gran Senor (8-11, 1984), Tenby (4-5, 1993) and Entrepreneur (4-6, 1997) -- were all beaten.
Joseph O'Brien, the 19-year-old eldest son of Aidan O'Brien, takes the ride on Camelot.
Michael Church, the official historian of the Derby, has checked through his records and can confirm that if Aidan O'Brien and his son Joseph win the Derby with Camelot, they will be the first trainer/jockey father/son combination to do so. This is despite nine Derby winners having the same surname for trainer and jockey -- the various pairs of trainer and jockeys named Scott and Day were all brothers.
Astrology (8-1 with William Hill), partnered by Ryan Moore on Saturday, was the impressive 11-length winner of the Group 3 Dee Stakes at Chester on May 11. O'Brien saddled the first and second in 2002 when Hawk Wing was runner-up to High Chaparral.
Hayley Turner will become only the second female jockey to ride in the premier classic when partnering Cavaleiro (backed from 100-1 into 40-1 with William Hill) for trainer Marcus Tregoning.
Cavaleiro, a son of Tregoning's 2006 Derby hero Sir Percy, won twice as a juvenile before finishing third to Main Sequence on his seasonal reappearance in the Group 3 Derby Trial over 1 1/2 miles on Polytrack at Lingfield Park on May 12.
The strongest opposition to the Ballydoyle challenge may come from the Andrew Balding-trained Bonfire, the 9-2 second favorite with William Hill. The Manduro colt landed the Group 2 Dante Stakes at York on May 17, one of the leading trials for the Derby. Since the turn of the century, North Light (2004), Motivator (2005) and Authorized (2007) have completed the Dante/Derby double, while Workforce (2010) was successful at Epsom Downs after finishing runner-up at York.
Bonfire will be the first runner in the Derby for Andrew Balding, whose father Ian trained Mill Reef to success in 1971. Bonfire is due to be joined by stable companion Minimise Risk (66-1), who won a maiden at Newbury in April before finishing last of five in the Group 3 Chester Vase on May 10 on ground that did not suit.
Main Sequence, the 9-1 fourth favorite with William Hill, will be trainer David Lanigan's first runner in the Derby and comes into the race unbeaten in four starts. The Niarchos Family's colt registered his most recent success in the Lingfield Derby Trial. Regular rider Ted Durcan is booked again.
Another trainer set to saddle his first Derby runner is Richard Fahey, who has left in the well-traveled Mickdaam (25-1). The son of Dubawi finished fourth in the Group 2 U.A.E Derby at Meydan in March and entered the picture for the Derby when battling his way to success in the Group 3 Chester Vase earlier this month.
John Gosden enjoyed Derby success with Benny the Dip in 1997 and his runner this year is set to be Thought Worthy (16-1), who won the listed Fairway Stakes at Newmarket on May 19 when Rugged Cross (50-1) was a length back in third. Rugged Cross is trained by Henry Candy, who sent out the 1980 runner-up Master Willie.
Andrew Cooper, Director of Racing and Clerk of the Course at Epsom Downs Racecourse, was satisfied with the field.
"The Investec Derby is all about producing the best horse," Cooper said. "Nearly all the trial winners are running and I am not looking at the race and saying which horse is missing.
"I have been quite comfortable with 13 (2011) and 12 (2010 and 2009) runners recently in the Investec Derby, as there is less potential for hard-luck stories.
"When Nijinsky won in 1970 there was a field of 11. When you have a potentially outstanding horse, as we have in the QIPCO Two Thousand Guineas winner Camelot, the desire to take him on with outsiders does not seem to be there maybe as much. So I am not unduly concerned with having nine runners on Saturday."
The going at Epsom on Thursday afternoon was good, good to firm in places. Watering continues as Wednesday and overnight saw dry weather. It is forecast to be cooler and cloudier. Although there could be a chance of a shower Thursday night, it's likely to remain mainly dry up to and including Saturday.
"The rain never came yesterday, though there were showers in the area," Cooper said Thursday. "We weren't banking or depending on showers anyway. In terms of watering, it is a question of fine tuning. We are putting three millimeters of water on the home straight this afternoon.
"The ground remains good, good to firm in places. It is predominantly good ground, certainly from the Derby (12-furlong) start down to the beginning of the straight (3 1/2 furlongs out).
"It is quicker in places in the home straight and in some areas of the climb up the back. We are saving ground for Saturday on the inside from the mile start down to the winning post, by moving the rail out by up to six yards tomorrow (Friday).
"You wouldn't be far away from calling the ground good, but with dry weather, I think it's fair to call it good, good to firm in places. It's nice Flat racing ground.
"We started watering on Tuesday of last week and have not been putting big volumes on -- just keeping the ground at or near where it was.
"It is too early say whether we will water after racing tomorrow. We will see how much the course has dried up after racing tomorrow. With these sort of temperatures, I actually think there is a good chance we will leave it alone."