St. Louis ? When Affirmed won the Belmont Stakes in 1978, winning horse racing’s Triple Crown was starting to look downright routine.

It was the second straight year — and the third time in six years — a horse had won the Kentucky Derby, the Preakness and the Belmont Stakes. Never before had horses won the Triple Crown in consecutive years (Seattle Slew had won in 1977), and it was just the 11th time ever it had been accomplished.

It also marked the last time anyone has won it. Since then, no horse has been able to win the three races, sandwiched into a grueling five-week span in the spring. It has now been 26 years since Affirmed’s Triple Crown, giving the sport its longest Crown-less run since Sir Barton first pulled off the feat in 1919.

Only one horse still has a chance at the Triple Crown, Kentucky Derby winner Smarty Jones. Wednesday, Smarty Jones was made the 8-5 morning-line favorite for the second jewel, Saturday’s Preakness, and the chances of there being another Triple Crown winner can’t yet be discarded.

“It’s not impossible,” said Hall of Fame jockey Chris McCarron, who almost won the Triple Crown on Alysheba in 1987, “but it’s very difficult to achieve.”

Jack Knowlton, one of the owners of Funny Cide, who won the Kentucky Derby and the Preakness last year before losing in the Belmont said, “It’s like our trainer, Barclay Tagg, said, ‘One thousand things have to go right, only one has to go wrong.'”

Close, but no cigar

The Triple Crown drought has been even more noticeable recently because there have been so many close calls. Since 1997, five horses have won the first two legs but lost in the Belmont. Horses keep knocking on the door but are finding admittance to the sport’s most exclusive club difficult.

There are several reasons put forth as to why the absence of a Triple Crown winner has reached record lengths. The simplest is that, in any case, it’s not an easy thing to do. Consider that the previous longest run without a winner, the 25-year span between Citation in 1948 and Secretariat in 1973, was bookended by two of the greatest horses in the sport’s history.

“There hasn’t been a horse that has been as good as those” who have won it, said Jay Privman, national correspondent for Daily Racing Form, the industry’s bible. “You look at who won, it’s an all-star list. The horses that have come up short recently, like Funny Cide or Charismatic, in hindsight, they didn’t deserve to win the Triple Crown. They were nice, but they aren’t among the all-time greats.

Kentucky Derby winner Smarty Jones is washed by groom Mario Arriaga after a workout. The horse, which practiced Thursday at Pimlico in Baltimore, could become the first Triple Crown winner since 1978 with wins Saturday in the Preakness and next month at the Belmont Stakes.

“If you look back at the winners, they’re all-time greats, not horses that got hot for five weeks. Affirmed, Seattle Slew, they went on to be great 4-year-olds. There haven’t been horses of that caliber.

Less hardy horses?

And that leads to another reason there hasn’t been a Triple Crown winner for so long. The Triple Crown races, among the oldest in the sport, haven’t changed, but the horses may have.

“I’m not exactly sure what caused the drought between Citation and Secretariat,” McCarron said, “but I’m inclined to think that (now) horses may not be quite as hardy as they once were. I don’t know if horses could stay in training and withstand the kind of training that they used to.”

That’s clear to see. Horses today just don’t run three races in five weeks, at least not against top competition. When Citation won the Triple Crown in 1948, he raced in the Jersey Derby between the Preakness and Belmont (which at the time were four weeks apart), something that would be unheard of now. In all, Citation raced 20 times as a 3-year-old; that’s a full career for horses today.

When Charismatic broke down in the final furlong of the 1999 Belmont needing a win for the Triple Crown, it was his fifth stakes race in nine weeks and trainer D. Wayne Lukas was criticized for overworking the horse.

With thoroughbreds running less often, winning three races in five weeks is tough, especially since the rules are stacked against the Kentucky Derby winner. Horses that don’t win the Derby can skip the Preakness and be rested for the Belmont. Derby winners don’t have that option; to win the Triple Crown, they have to run — and win — all three races.

Preakness entry Lion Heart, with exercise rider Jean Claude up, is walked off the track at Pimlico by trainer Patrick Biancone. Lion Heart, who finished second in the Kentucky Derby, is one of the top challengers to Smarty Jones in the Preakness on Saturday in Baltimore.

That’s another reason for so many horses winning the first two legs: Many of the best 3-year-olds skip the Preakness after losing in the Derby.

“We got beat by two horses last year that skipped the Preakness,” Funny Cide’s Knowlton said. “If you look back at Affirmed and Alydar (which came in second in all three races in 1978), you can’t tell me that if Alydar skipped the Preakness he wouldn’t have won the Belmont.”

‘Great ones do it’

And finally, things just happen. With every close call, there’s a different reason for the failure. War Emblem stumbled at the start of the 2002 Belmont and never caught up. In 1998, Real Quiet and Victory Gallop ran nose to nose down the stretch, with Victory Gallop winning by the bob of a head.

In 1997, jockey Gary Stevens and trainer Bob Baffert both said that their horse, Silver Charm, was so busy battling Free House down the stretch that it didn’t see a faster horse, Touch Gold, coming by on the outside until it was too late. Spectacular Bid may have been done in by stepping on a safety pin before the ’79 Belmont. McCarron was criticized for his ride on board Alysheba in ’87.

In the end, all failed, and that’s what makes the Triple Crown what it is, an affirmation of racing excellence.

“In hindsight,” Privman said, “the great ones do it and the very good don’t.”