Shackleford led from the start, but when the field of 12 turned for home in the 1½-mile Belmont, he began tiring in the muck as long shots Stay Thirsty and Ruler On Ice closed in. It was Ruler On Ice, under Jose Valdivia Jr., who splashed home first, three-quarters of a length ahead of Stay Thirsty.
The much-hyped rubber match between Shackleford and Kentucky Derby winner Animal Kingdom never developed. Shackleford finished fifth, while Animal Kingdom got off to a terrible start, never got into contention and finished sixth.
Jockey John Velazquez nearly fell off when Animal Kingdom collided with Monzon just after the start. He somehow managed to get his left foot back into the stirrup, but by then it was too late. Animal Kingdom fell more than 12 lengths behind Shackleford, and did well to finish in the middle of the pack.
An elated Valdivia, riding in his first Belmont, described the final seconds before crossing the finish line.
"I'm a couple of yards from the wire and I'm thinking, `Oh my god, oh my god, I'm going to win the Belmont,"' he said.
Ruler On Ice's victory makes it three years in a row a different horse has won each of the Triple Crown races, and next year it will be a 33-year gap since Affirmed swept the Derby, Preakness and Belmont in 1978.
Ruler On Ice, trained by New Jersey-based Kelly Breen, did not run in the first two legs of the Triple Crown. The 3-year-old gelding didn't have enough graded stakes earnings to qualify for the Derby, but vindicated his trainer's faith by defeating a field that included the first seven finishers in the Run for the Roses.
The winning time for the oldest and longest race in the Triple Crown was a slow 2:30.88.
Ruler On Ice returned $51.50, $26 and $13.60. Stay Thirsty, owner Mike Repole's second-best 3-year-old behind the sidelined Uncle Mo, paid $19.40 and $10.80. Brilliant Speed was third and returned $7.90 to show.
Nehro, second in his last three races, including the Derby, was fourth, followed by Shackleford, Animal Kingdom, Mucho Macho Man, Santiva, Monzon, Master of Hounds, Prime Cut and Isn't He Perfect.