LOUISVILLE, Ky. -- Bode Baffert has never been so nervous about a race. The 7-year-old son of Hall of Fame trainer Bob Baffert is the namesake of the 138th Kentucky Derby morning-line favorite, Bodemeister.
"Bode feels a lot of pressure right now," Baffert said. "I said, 'Isn't it exciting, Bodemeister's going to go to the Derby?' And he said, 'Well, what if he loses?'
"You never know, but at least you have a good horse named after you. He didn't know what to think of it."
Bodemeister, at 4-1 odds, is among a 20-horse field that's so stacked that unbeaten Gemologist, trained by Todd Pletcher, is no better than third choice on the morning line behind Union Rags.
"History tells us that you can't throw anyone out," said Pletcher, a former D. Wayne Lukas assistant who is also starting El Padrino. "There have been some winners the past few years that have been way down everybody's depth charts."
Still, just because the odds are big doesn't mean there aren't some serious contenders like I'll Have Another at 12-1 or, at 15-1, Take Charge Indy, who will leave from the No. 3 post with jockey Calvin Borel, a three-time Derby winner.
"This is the best bunch I've seen in a long time," said Lukas, a four-time Derby-winning trainer. "I was out there riding next to some of them, and let me tell you, this is a hell of a group."
Some of the strongest contenders -- Hansen, for example -- have had the most success running at or near the pace. But their task is complicated by the presence of speedster Trinniberg, who could prove to be enough of a pest on the front end to compromise any horse willing to keep pace with him.
If the early fractions in the 1¼-mile race are fast enough, it could set up well for a deep closer like Dullahan, Daddy Nose Best or I'll Have Another.
Baffert, who has won the Derby three times and also has long shot Liaison in the field called it "one of the toughest Derbys I've been in probably the last 10 years."
Baffert has a new outlook on life after a medical scare in March when he was hospitalized with a heart attack in Dubai.
Bodemeister, ridden by Hall of Fame jockey Mike Smith, goes into the starting gate staring down 129 years of Derby history. The last horse to win without racing as a 2-year-old was Apollo in 1882.
"I've brought some really good horses here, and they were the best horse, but they got beat," he said, referring to Lookin At Lucky, the 2010 race-day favorite who was trapped on the rail and finished sixth. In 2001, his heavy favorite, Point Given, wound up fifth.
Union Rags, the 9-2 second choice ridden by Julien Leparoux, is the best horse trainer Michael Matz has brought to the Derby since he won with undefeated Barbaro in 2006.
"I was lucky enough once," he said. "It's hard to believe you can get lucky twice."
Matz trains the strapping colt for Phyllis Wyeth, the former steeplechase rider who was paralyzed from the waist down in a 1962 car accident and gets around in a wheelchair. She is married to painter Jamie Wyeth, whose father was renowned Andrew Wyeth.
Gemologist, undefeated in five races, is trained by 2010 Derby winner Pletcher, yet he's been overshadowed by the other entrants since arriving late in Louisville on Tuesday, getting most of his training in Florida.
"He's done everything he could possibly do," Pletcher said, "but part of it might be because the 2-year-old races he ran in weren't the Breeders' Cup races. He was a little late in developing."
Two of Gemologist's wins came at Churchill Downs.
Hansen is a standout on looks alone. The colt is nearly white and his outspoken owner Kendall Hansen tried to doll him up by having his tail painted blue for the Blue Grass three weeks ago. The track stewards didn't approve and neither did trainer Mike Maker.
Nine horses are expected to start from November's Breeders' Cup Juvenile that Hansen won by edging out a hard-charging Union Rags, proof of the depth of this field.
"It's amazing how well the major contenders have held their form," trainer Steve Asmussen said. "It's a very competitive race, and there are some very good horses."
Like Baffert and Pletcher, Asmussen has two horses in the Derby -- Daddy Nose Best and Sabercat. He came close last year when Nehro finished second to Animal Kingdom.
"It is definitely on the bucket list," Asmussen said. "I like my horses, love how they're doing, feel that they're going to run real good Saturday, but have no control over everybody else."
Trainer Graham Motion, jockey John Velazquez, and Barry Irwin, who heads the Team Valor ownership group, shared last year's win with Animal Kingdom. They return with 20-1 shot Went the Day Well, trying to become the first connections to repeat since 1972-73 when Riva Ridge and Secretariat prevailed.
Then there's the weather.
Saturday's forecast calls for a high of 86 with a 30 percent chance of showers and thunderstorms. The Derby day temperature has topped 80 degrees just five times since 1969, when it hit 87.
Making it feel subtropical is the humidity, which was close to 70 percent on Friday. The heat combined with humidity affects horses in different ways. Some sweat profusely; others handle the elements. All Derby horses will be examined by vets on race morning.
"The hot weather may be to our advantage," said Mark Casse, who saddles 30-1 shot Prospective. "There are some hot-headed horses in this field that it could hurt. My horse stays calm and cool."
Post time is 6:32 p.m. ET.