"You need the racing luck," suggests Bob Baffert, the only trainer to lose the Belmont three times with horses that won the first two legs.
It's tougher these days because of changes in breeding, full fields of 20 horses in the Kentucky Derby, more foals and an increased emphasis by owners and trainers on the sport's three biggest races.
I'll Have Another, an average-sized chestnut colt, appears to have rebounded well after two hard races in the Derby and Preakness, with the most exhausting still to come. He'll run 1 1-2 miles around Belmont's oval with 11 rivals gunning to keep history from happening.
Before Affirmed swept the 1978 Kentucky Derby, Preakness and Belmont, 25 years had passed between Citation in 1948 and Secretariat in 1973.
Ask trainers and jockeys what makes winning the Triple Crown so difficult, and no one can agree on a single factor.
Real Quiet had no luck in 1998, when a nose separated him from racing immortality. The year before, Baffert watched from the stands as Silver Charm lost by three-quarters of a length. In 2002, War Emblem nearly fell to his knees when the starting gate sprang open, and Baffert knew right then the colt was doomed. He straggled home in eighth place, beaten 19 1-2 lengths by a 70-1 shot.
"Everybody is trying to take their little shot at you," Baffert said.
When Sir Barton became the first horse to sweep the Kentucky Derby, Preakness and Belmont in 1919, the phrase Triple Crown hadn't been invented. And he wasn't even the most popular horse of his era; that mantle belonged to Man o' War, who won nine of his 10 starts as a 2-year-old but didn't run in the Derby the next year.
Sir Barton had just two opponents in the Belmont, which was then run at 1 3-8 miles. His winning time of 2:17 2-5 was an American record.
After him, the Triple Crown was won in bunches.
Three horses accomplished the feat in the 1930s, four did it in the '40s, and three more pulled it off in the '70s. The current 34-year drought began after Affirmed outdueled Alydar to sweep the series in 1978.
In 1930, Gallant Fox won the Preakness, which was run a mere eight days before the Kentucky Derby. The bay colt easily won the Derby, but wasn't the favorite in the Belmont. Even so, he led wire to wire, and by then, the Triple Crown moniker was attached to the three races.
The Belmont took a toll on War Admiral in 1937.
A son of Man o' War, he won by three lengths but not without theatrics. He acted up at the start and repeatedly crashed through the gate, delaying the race for almost nine minutes. Then he stumbled at the start and sliced off a piece of his right front heel, leaving behind a trail of blood. He came up lame, but returned to racing that fall.
In 1943, Count Fleet had just two opponents in the Belmont, and he crushed them both. He won by 25 lengths, a record that stood until Secretariat's 31-length victory in 1973.
Breeding has changed over the years, with speed replacing stamina as the top priority.
"Back in the '70s we were still breeding horses to race them and so much of the industry now is concentrated on sales," said Penny Chenery, who owned Secretariat. "And so you breed a precocious, good-looking, early speed horse who isn't equipped to go a mile and a half, or to run three hard races in five weeks."
Another reason a Triple is so difficult is the greater emphasis on the series. Owners know that a winner of any of the race, much less all three, can command huge prices in the breeding shed, while trainers can burnish their credentials with multiple wins.
A lot more horses are eligible for the Triple Crown these days, too.
There were just 2,128 foals the same year as Sir Barton; 32,187 thoroughbreds were born three years ago, and only 20 of those earned enough money to qualify for the Kentucky Derby.
Barclay Tagg, who oversaw Funny Cide's failed Triple bid in 2003, doesn't believe it's anything in particular about the Belmont that does in potential history-makers, but rather the tight schedule of winter prep races followed by the three races in quick succession.
"Before those murderous five weeks come up, you've got to be in probably three preps against much tougher competition." Tagg said. "Races like the Florida Derby, the Wood, the Fountain of Youth, the Louisiana Derby, they are major races and take a lot out of you."
Nicknamed "The Test of the Champion," the Belmont is uncharted territory for 3-year-olds who have never run that far and likely won't again.
"It's such an odd distance in American racing," said trainer Dale Romans, who will saddle Dullahan on Saturday. "I don't think any of us have a really good handle on it."
Doug O'Neill, who trains I'll Have Another, said, "I don't think you can take a horse that can't get a mile and a half and do anything special training-wise to make him get a mile and a half. It's just a matter of how they're feeling that day."
Jockeys aren't used to riding races that long, either. The Belmont has undone both rookies and Hall of Fame riders alike. Some have mistakenly moved too soon and burned out their horses before the 1,097-yard stretch run. Others have moved too late and let the leaders get away.
"More riders lose this race than horses," said trainer D. Wayne Lukas, a four-time Belmont winner who lost a Triple Crown attempt with Charismatic in 1999.
The deep, sandy surface can prove tiring to run on, the turns are sweeping, and the poles used by jockeys to judge their location are placed differently than at the mile tracks where most of them ride.
"It's very deceiving," said Mike Smith, who is 1-for-13 in the Belmont and will be aboard Paynter on Saturday. "Where the half-mile pole is on a normal track, it's the three-quarter pole at Belmont, so it can throw you off. You can use those big turns to do different things and throw a race wide open depending on the pace."
I'll Have Another's California-based jockey Mario Gutierrez planned to ride a few races at Belmont on Friday for practice before the big day.
In the Belmont, I'll Have Another will break from the No. 11 post, with most of the field inside of him, giving Gutierrez room to position his colt out of trouble early. What happens the rest of the way is left to chance.
"The ifs have to happen," Baffert said.
The field for Saturday's 144th Belmont Stakes, with post position, horse's name, jockey's name and odds:
1. Street Life J. Lezcano 12-1
2. Unstoppable U J. Alvarado 30-1
3. Union Rags J. Velazquez 6-1
4. Atigun J. Leparoux 30-1
5. Dullahan J. Castellano 5-1
6. Ravelo's Boy A. Solis 50-1
7. Five Sixteen R. Napravnik 50-1
8. Guyana Star Dweej K. Desormeaux 50-1
9. Paynter M. Smith 8-1
10. Optimizer C. Nakatani 20-1
11. I'll Have Another M. Gutierrez 4-5
12. My Adonis R. Dominguez 20-1
P Saturday, 4:30 p.m. post time, TV • Ch. 5