If last year's Kentucky Derby was the story of a people's champion from unlikely origins — California Chrome — Saturday's race appears to shape up as a battle of heavyweight trainers and star horses who have so far lived up to their billing.
The spotlight at Churchill Downs will center on Bob Baffert's traditional Barn 33, where the Hall of Fame trainer will prepare a one-two punch the likes of which the sport has rarely seen. Baffert's American Pharoah is expected to be the favorite in the $2 million race after a prep season in which the bay colt simply ran away from his competition. But plenty of handicappers are partial to his stablemate, the lanky Dortmund, who won his prep races nearly as impressively against tougher competition.
With the usual field of 20 expected for the 141st running of the Derby, both of Baffert's stars will likely have to overcome difficulties they've never encountered if one is to bring the trainer his fourth Derby win and first since 2002.
Baffert's rival for training supremacy, Todd Pletcher, will saddle his own dynamic duo in Carpe Diem, a horse talented enough to be the favorite many years, and Materiality, who didn't run as a 2-year-old but won the Florida Derby impressively.
Also included in this stacked field are Wood Memorial winner Frosted and battle-tested contenders Firing Line and International Star.
With handicappers already comparing this group of 3-year-olds to the best crops in recent history, here are five key storylines headed into the race:
Which Baffert horse is the best?
For all the elite Triple Crown contenders he's trained in his career, Baffert has never gone into a Derby with a pair quite like this.
Handicappers fixed their eyes on American Pharoah as a potential Derby favorite heading into prep season, and the colt pulled off the rare trick of actually exceeding expectations. Baffert and jockey Victor Espinoza were hoping American Pharoah would be tested in the April 11 Arkansas Derby, but he went so fast that he won by eight lengths despite Espinoza's easing off down the stretch.
Just a week earlier, however, the undefeated Dortmund looked nearly as good winning the Santa Anita Derby by 4 1/4 lengths. He would likely have emerged as the Derby favorite in most of the past 20 years.
Those who prefer Dortmund, ridden by Martin Garcia, note that he twice defeated another top contender, Firing Line. American Pharoah has not been pushed in the same fashion, and some wonder how he'll respond if he can't run away from the competition.
Both horses like to run near the lead, so the tactical battle between jockeys Garcia and Espinoza, who won aboard California Chrome last year, could also prove fascinating.
This sets up as the best intra-barn duel in recent memory.
Which horse is most likely to challenge Baffert's duo?
The most popular choice is Pletcher's Carpe Diem, another sensational talent with a record of excellent performances in the prep races.
WinStar Farm and Stonestreet Stables paid $1.6 million at auction for the 2-year-old Carpe Diem, suggesting they saw great promise. And he's met expectations, most recently winning the April 4 Blue Grass Stakes by three lengths.
In another sign of Carpe Diem's talent, Hall of Fame jockey John Velazquez opted to ride him in the Derby rather than fast-improving stablemate Materiality. Velazquez had steered both horses through prep season. But Javier Castellano will take over Materiality on Saturday.
Analysts are generally wary of Derby contenders who didn't run as 2-year-olds, but Materiality has plenty of people buzzing about his chances. Despite his inexperience, he outdueled another solid contender, Rick Violette's Upstart, in the Florida Derby. And he impressed Pletcher by bounding back quickly with impressive workouts in Florida.
Frosted also stamped himself a threat to American Pharoah and Dortmund with a win in the April 4 Wood Memorial that ranked among the most impressive performances of the prep season. He's a versatile horse, which often bodes well in the chaos of the Derby. And trainer Kiaran McLaughlin seemed to find the right formula with a new jockey, Joel Rosario, after Frosted mysteriously lost focus in the Feb. 21 Fountain of Youth Stakes.
Does this field bring the potential for a memorable rivalry?
So it would seem.
The sport has been short on Triple Crown rivalries in recent years, partly because so many trainers opt against entering the Preakness if their horses don't win the Derby.
We haven't seen an epic three-part duel since Sunday Silence and Easy Goer battled in 1989. But racing lovers, raised on tales of Affirmed and Alydar, always dream of another great trilogy.
Could Baffert's horses author a story of brilliant intramural competition? Could Carpe Diem go head to head with either American Pharoah or Dortmund and set up a multirace battle between Baffert and Pletcher, the leading trainers of this era?
Given the difficulties presented by a 20-horse field, we have no idea whether any of these storylines will hold past Saturday. But the potential is there.
Which contenders seem best positioned to upend conventional wisdom?
This is a deep field, so there are plenty of answers. The most interesting might be Mubtaahij, the rare Derby contender who made his reputation entirely outside the United States. Mubtaahij won the UAE Derby in Dubai by eight lengths, and his South African trainer, Mike de Kock, is widely regarded as one of the best in the world.
Handicappers wonder how Mubtaahij will react to the dirt in Louisville and how Belgian jockey Christophe Soumillon will navigate the crowded field.
But Mubtaahij will bring an intriguing whiff of the unknown.
It would also be a mistake to write off Firing Line or Upstart, despite prep losses to the other top contenders, or to ignore International Star, undefeated this year even though the Mike Maker-trained colt is generally regarded as a lesser physical talent than the top choices.
Could this be the best Derby field in recent memory?
That seems to be the consensus view. Generally, this time of year brings a lot of moaning and groaning about the state of the 3-year-old crop.
But 2015 has been quite the opposite, with handicappers reaching back to the 1970s and 1980s for comparisons.
The top contenders combine rich pedigrees, elite trainers and standout prep performances. Analysts have spent the past few weeks saying any one of American Pharoah, Dortmund or Carpe Diem would make a solid favorite in a typical year. And the rest of the field is crammed with intriguing choices to upset that trio.
The Derby is always exciting because of the stakes and the unpredictability. But within the racing world, there's extra anticipation for the 141st running.