It's the longest dry spell in history.
Everyone who loves the sport has a theory on why a 3-year-old thoroughbred hasn't been able to sweep the Kentucky Derby, Preakness and Belmont.
Changes in breeding. A tougher road to the Derby. Bigger fields in the three races.
And then there's luck.
"It takes a special horse," said Steve Cauthen, who rode Affirmed in 1978. "And you need things to not go wrong for you."
It's not impossible, or at least it wasn't.
Since Sir Barton won what later became known as the Triple Crown in 1919, 10 other thoroughbreds have completed the feat, including three each in the '30s, '40s and '70s. Most recently, Secretariat set track records on the way to his sweep in 1973, followed by Seattle Slew in '77 and Affirmed the next year.
Back then, the question was whether the series had become too easy. Not anymore.
Sure, there have been 11 Triple possibilities since Affirmed, and there could have been 12 except that I'll Have Another was scratched the day before the Belmont last year with a tendon injury.
Hopes were dashed again this year, as Kentucky Derby winner Orb lost in the Preakness to Oxbow, leaving Saturday's Belmont Stakes almost an afterthought despite its $1 million purse.
"It would be great for racing if a horse wins it and at the same time the fact no one has been able to do it for so long makes it that more exciting, that much more intriguing," said trainer Todd Pletcher, who won the 2010 Derby with Super Saver.
The Triple Crown is run on a compressed schedule, just five weeks from start to finish. Each race varies in distance, from 1 1/4 miles at the Derby to 1 3/16 miles at the Preakness to 1 1/2 miles at the Belmont different tracks and crowded fields, with 20 horses typically contesting the rough-and-tumble Derby.
To understand what a Triple try means to racing fans, just look at Belmont attendance.
The track on Long Island might draw in the neighborhood of 50,000 fans when racing's greatest prize isn't on the line.
But when it is, the numbers soar.
From 2002-04, the race attracted its three largest crowds more than 100,000 each year and in 2008, more than 94,000 packed Belmont Park only to see Big Brown fail to finish his Triple bid as Da'Tara pulled off an upset.
Those years also netted the most eyeballs for NBC and ABC's telecasts of the race. The networks posted monster viewership each year, with the highest number of 21.86 million tuning in for Smarty Jones' attempt in 2004. The small chestnut colt helped bring in a record 120,139 fans to Belmont that day.
Seattle Slew is the only Triple Crown winner to account for one of the top-10 crowds on Belmont day. His winning bid in 1977 attracted 71,026 back when the feat wasn't as publicized because TV was primarily three channels, cable was in its infancy, and the Internet and social media didn't exist.
That's not all that has changed about the racing landscape. Tracks were once among the few outlets for gambling but now casinos dot the landscape, wagers can be placed online from home, poker tournaments air in prime time and lottery jackpots are in the hundreds of millions.
It's easy to make a case that it's become harder to win a Triple Crown since the 1970s, too.
Under a new system instituted this year by Churchill Downs, there is increased pressure to qualify for the Kentucky Derby by racking up points in designated races. If a horse doesn't have enough points, then those prep races turn into must-wins. Qualifying was previously based on earnings in graded stakes races, a bigger pool.
Hall of Fame trainer D. Wayne Lukas, who owns a record 14 victories in Triple Crown races, views the series as five races, including a couple of preps, instead of just the Derby, Preakness and Belmont.
"It's becoming increasingly more difficult to perform," he said. "You can't take a soft approach to the Derby. You've got to have two or three tough races to get into the darn thing. When you get here (at the Derby), you've used up a certain amount of energy."
Still, horses today have lighter schedules than their ancestors, with trainers choosing to run their horses sparingly and allowing ample time between races.
Orb made just three starts this year before winning the Derby, typical of many Triple Crown contenders. Verrazano, who finished 14th in the Derby, didn't run at all as a 2-year-old.
"They don't seem to be overall quite as tough or durable as horses in the past," said Cauthen, who now breeds horses on his farm in Verona, Ky. "Affirmed ran nine or 10 times as a 2-year-old and he thrived on his racing.
"Thirty years ago, it was nothing to race a horse every couple of weeks and sometimes you might race them twice in a week. You don't see that much anymore. I'm not saying they're wrong, but it's a different mindset. They want their horses to be as fresh as possible and are priming them for a certain race, and some of the horses are racing just four or five times (overall) before they get to the Derby."
By comparison, 1948 Triple Crown winner Citation raced 16 times before the Kentucky Derby. Secretariat raced 12 times before the Derby, while Seattle Slew raced six times.
"I have so much respect for those (11) horses," Hall of Fame trainer Bob Baffert said. "They were not only fast and really good horses, they were made of iron."
Trainers have to adjust their methods to their horses, making sure the four-legged athletes are rested yet fit enough to run on the three big days.
"Once you get into the Triple Crown series then it is really difficult to keep the energy level up, the soundness, keep them focused and keep them happy," Lukas said. "Time is your ally when you're training horses and you don't get it. If we had more spacing it would be a lot easier. It makes it difficult and that's why the Triple Crown is such a special and hard-to-achieve honor."
Breeding has changed since the glut of Triple Crown winners in the 1970s, when the industry was focused on breeding horses to race them as opposed to today's emphasis on sales.
"I think that's legitimate and that goes to the whole sales theory that you have to have something perform quickly for the new buyer," said Ogden Mills "Dinny" Phipps, a prominent breeder and co-owner of Orb. "That can be a small thing, but I don't think it's THE reason."
While foal crops are greater these days, the number of horses being bred and trained to race has been dropping in the last five years due to the recession, reduced purse money, breeding fees and sales prices.
"The guys in Kentucky have figured out that the horses that sell well, those are the ones they want to breed," Lukas said. "They don't get too concerned about step two, that's how are they going to turn out as racehorses. They want them to look good, and they breed them that way."
Yet even with racing de-emphasized, the horses competing for the Triple find the going tougher. Previous winners faced much smaller fields, creating fewer traffic problems.
"I don't like 20-horse fields," Phipps said. "I don't think it's fair on the horse, and I don't think it always creates the right winner."
Only Omaha (1935), War Admiral (1937) and Assault (1946) began their Triple Crown bid in a Kentucky Derby that had more than 15 starters.
Affirmed faced 22 rivals in the whole series. Big Brown? Try 38.
There also have long been questions about how medications affect racing, not only illegal drugs but those allowed on race day, including Lasix, an anti-bleeding medication. There has been a movement to ban Lasix in the U.S. like it is in other countries but prominent Kentucky veterinarian Dr. Larry Bramlage doesn't think it has affected the Triple Crown.
"I don't think on that issue that it's played any role at all," he said. "It's duration is so short-lived that as long as the horse is eating a normal diet and has access to water, it would never have a residual effect from the Derby to the Preakness and to the Belmont Stakes to affect the likelihood of a Triple Crown winner."
Bad racing luck, however, has done in some potential history-makers.
A nose was all that separated Real Quiet from racing immortality. He was beaten by the smallest of margins in the 1998 Belmont, when Victory Gallop stuck his nose in front at the wire.
"Real Quiet is the one I've always felt got away from me," said Baffert, who also had his Triple Crown hopes dashed in 1997 with Silver Charm. "He was ready to do it."
On the morning of the 1979 Belmont, a safety pin was discovered embedded in Spectacular Bid's hoof. He didn't appear lame, so he ran in the race. His teenage jockey, Ron Franklin, gunned the colt to the early lead before he eventually faded to third.
In the end, it may just come down to waiting for a horse that's more durable and tougher than all the competition.
"We haven't had a dominant horse like Secretariat or Slew lately," Lukas said. "We'll get a Triple Crown winner when we get a dominant horse."
Until then, expect owners, trainers and jockeys to keep chasing the dream.
"I guess it is (disappointing) with the fans," said Orb's trainer, Shug McGaughey, "but it's not to me because there's always the pursuit. It makes you want it more."
AP Sports Writers Gary Graves and Richard Rosenblatt, and AP freelancers Josh Abner and Mike Farrell contributed to this report.