ELMONT, N.Y. – When the gates open for Saturday’s Grade 1, $1 million Belmont Stakes at Belmont Park, 1 ½ miles will be standing between any one of a dozen thoroughbreds and the right to claim the title as the 143rd winner of the “Test of the Champion.”

But for Kentucky Derby winner Animal Kingdom and Preakness hero Shackleford, much more is at stake in the oldest and longest leg of racing’s Triple Crown.

For the 22nd time in history, the Belmont Stakes will serve as the rubber match between the individual winners of the first two races in the Triple Crown. The scorecard, in terms of Belmont wins, reads Preakness 10, Derby 5, with Afleet Alex the most recent Preakness winner to vanquish the Derby victor, taking the 2005 Belmont in which Giacomo, longshot winner of the Run for the Roses, finished seventh.

One has to go back to 1984, when Swale bested Preakness winner Gate Dancer, for a Belmont in which the Derby winner emerged victorious in a showdown. In spite of history, Animal Kingdom was tabbed the 2-1 favorite by The New York Racing Association, Inc. (NYRA) oddsmaker Eric Donovan, with Shackleford the third choice at 9-2 in the 12-horse field.

The Triple Crown itself has been unclaimed since 1978, when Affirmed became the 11th 3-year-old colt to sweep the series, and in the absence of a try for the most elusive of racing’s prizes, the excitement created by the face-off between Animal Kingdom and Shackleford has been considerable.

“Without a Triple Crown on the line, this is going to be one of the most exciting Belmonts I can remember,” declared Shackleford’s trainer, Dale Romans.

Adding to the buzz has been the verbal sparring between the connections of Animal Kingdom, a chestnut with a white star on his handsome face, and Shackleford, a striking chestnut with a big white blaze.

At the Belmont Stakes Media Luncheon on Tuesday, Animal Kingdom’s owner Barry Irwin, the outspoken founder and CEO of Team Valor International, whose crimson and green colors Animal Kingdom carries, dissed the Preakness winner, saying he was not at all worried about Shackleford. Instead, said Irwin, he thought the main competition for Animal Kingdom would come from Mucho Macho Man, third in the Derby and sixth in the Preakness after losing a shoe.

Undeterred, Romans retorted: “That may not be the stupidest thing Barry’s ever said, but it’s close.”

Animal Kingdom, who has earned more than $1.9 million, will be making his third start on dirt in the Belmont, having won the Derby by 2 ¾ lengths at odds of 20-1 under jockey John Velazquez, and finishing second by a half-length to Shackleford in the Preakness on May 21. At Pimlico, the son of Leroidesanimaux broke slowly and spent the first part of the race dwelling in the back of the pack, getting dirt kicked in his face for the first time in his career.

“I’ve never had a horse come back from a race like that; the dirt was literally caked in his blinkers,” said H. Graham Motion, Animal Kingdom’s trainer, whose charge drew post 9. “It was extraordinary. I don’t think that’s going to happen in the Belmont.”

In the Derby, the front-running Shackleford left from post position 14 and led to the quarter-pole through moderate fractions but couldn’t hold off Animal Kingdom, runner-up Nehro and Mucho Macho Man to finish fourth. He ran a slightly different race in the Preakness, bobbling at the start from post 5 and shadowing Flashpoint through a quick half-mile in 46.87 before taking over for good with a little more than a quarter-mile to go.

In the Belmont, Shackleford drew post position 12 under Jesus Castanon.

“In a 1 ½ mile race like the Belmont, the post position isn’t that important,” said Romans. “With post position 12, he’ll be the last one in and the first one out. Hopefully, he’ll be able to clear the field. He’s fast enough that he’ll be able to break and clear everyone anyway.”

The first seven finishers in the Derby, along with Stay Thirsty, who was 12th, all are returning in the Belmont. Nehro, the slight second choice on the morning line at 4-1, was 2 ¾ lengths behind Animal Kingdom in second at Churchill Downs. He then skipped the Preakness to freshen up for the Belmont.

“We’ve got three seconds in the last three Derbies, being Louisiana, Arkansas and Kentucky, and we hope to shed the bridesmaid’s tag and get the win,” said Brad Weisbord, racing manager for Zayat Racing LLC. “Nehro is very versatile, so he really can be anywhere.”

Trained by Steve Asmussen, who was second in the 2007 Belmont with eventual Horse of the Year Curlin, Nehro will be ridden by Corey Nakatani from post 6.

Along with Animal Kingdom and Shackleford, Mucho Macho Man is the only other Belmont entrant who will have competed in all three legs of the Triple Crown. Trained by heart transplant recipient Kathy Ritvo, Mucho Macho Man has been outfitted with a new pair of glue-on shoes, has a new rider in NYRA’s leading jockey, Ramon Dominguez, and his connections are eager for another shot at the top two.

“We think we have the best horse in the country,” said co-owner Dean Reeves. “We just need to prove it, and hope Saturday we’ll do that.”

Mucho Macho Man, who drew post 10, is 10-1 on the morning line.

Master of Hounds, based in Ireland and trained by Aidan O’Brien, finished fifth in the Derby and has made yet another Atlantic crossing for the Belmont. The Kingmambo colt is hoping to be the first horse since the Dermot Weld-trained Go and Go in 1990 to win the Belmont coming off the plane, having arrived in New York on Tuesday.

“He’s been training very, very well since the Derby,” said T.J. Comerford, O’Brien’s assistant, of Master of Hounds. “He’d never actually run on the dirt before he cantered around on the dirt at Churchill Downs. He’ll definitely put up a good show here. The 1 ½ miles will hit him on the head.”

Garrett Gomez, who was aboard for the Derby, rides Master of Hounds, 10-1 on the morning line, from the rail.

Santiva, who was gaining ground as he finished sixth in the Derby, is another who skipped the Preakness to focus on the Belmont. Trained by Eddie Kenneally for Tom Walters, Santiva will be making his fourth start of 2011 in the Belmont, having finished second to Mucho Macho Man in the Grade 2 Risen Star and ninth behind Brilliant Speed in the Grade 1 Blue Grass.

The Giant’s Causeway colt drew post position 4 for the Belmont, and will be ridden by Shaun Bridgmohan.

“He’s a horse that likes to just sit off the pace, and I think from there he can slide in and get nice and tight and be a horse or two off the rail,” said Kenneally’s assistant, Brendan Walsh. “Hopefully, there will be two or three in front of him; that would be ideal.”

Blue Grass winner Brilliant Speed was making his first start of the year on conventional dirt in the Derby, in which he came wide and made a late bid to finish seventh.

“He’s fresh and he runs well fresh,” said Tom Albertrani, who trains the homebred Dynaformer colt for Live Oak Plantation. “We’re enthusiastic about bringing him here for a 1 ½ mile race, considering his pedigree, and we thought we’d give it a shot with him on the dirt. There’s always a question how he’ll handle the surface, but I’m pretty optimistic.”

Joel Rosario will ride Brilliant Speed, 15-1 on the morning line, from post 5.

Stay Thirsty, winner of the Grade 3 Gotham Stakes at Aqueduct, is the final Derby veteran to return in the Belmont and owner Mike Repole is hoping for a home-track advantage for the Todd Pletcher-trained colt.

“Stay Thirsty obviously likes New York, he’s got two wins and two seconds,” said Repole, noting the Bernardini colt broke his maiden at Saratoga, where he also was second in the Grade 1 Hopeful at Saratoga Race Course. At Belmont, he finished second in his debut last July. “Being a New Yorker, this is the race I want to win.”

Javier Castellano rides Stay Thirsty, 20-1 on the morning line, from post 2.

Among the new shooters hoping to spring an upset is Prime Cut, most recently third in the Grade 2 Peter Pan at Belmont Park on May 14. The Bernardini colt, 15-1 on the morning line, drew post 8 and will be ridden by Hall of Fame jockey Edgar Prado, a two-time winner of the Belmont.

“We opted for the Peter Pan instead of the Preakness in anticipation of the Belmont,” said Ricky Giannini, assistant to trainer Neil Howard. “We think he’s more suited to the two turns than a one-turn, 1 1/8 mile race. We saw Drosselmeyer had some success in the Peter Pan and won the [2010] Belmont.”

Monzon, who finished sixth in the Peter Pan in his first start off a three-month layoff, drew post 7 under Jose Lezcano and was tabbed at 30-1 on the morning line.

“Our plan is to stick on the rail and wait,” said trainer Ignacio Correas, who will ship the Sagamore Farm colt to New York from Maryland the morning of the race. “Everyone wants to go to the first turn and get position, but you have plenty of time to win it or lose it. It’s 1 ½ miles.”

Ruler On Ice, 20-1 on the morning line from post position 3, is another who will ship in the morning of the race.

“I think we’ll be able to get where we want to get and leave it in [jockey] Jose Valdivia’s hands,” said trainer Kelly Breen from Monmouth Park.

Completing the field is Isn’t He Perfect, who was sixth in the Gotham and ninth in the Preakness in his most recent outing. At 30-1 on the morning line, Isn’t He Perfect will be ridden by Rajiv Maragh as he leaves from post position 11.

“I think it will be a fine position for him,” said trainer Doodnauth Shivmangal. “He’ll be outside, away from trouble and close to the pace.”

With a post time of 6:35 p.m. EDT, the Belmont Stakes will be the 11th of 13 races and will be telecast nationally on NBC beginning at 5 p.m., with coverage on VERSUS from 3-5 p.m. VERSUS will also carry post-race coverage from 7-7:30 p.m.