Big Brown straggled home tonight, losing the Belmont Stakes and the Triple Crown to 38-1 long shot Da’ Tara.

Da’ Tara went wire-to-wire, with 1-4 favorite Big Brown running third most of the way until his jockey, Kent Desormeaux, asked him for one of his explosive runs on the far turn.

He had nothing to give.

“I had no horse,” Mr. Desormeaux said.

Big Brown was eased up before he even finished the 1½ miles, the longest and toughest of the three classics.

His trainer, Rick Dutrow Jr., said all week long the horse’s victory was “a foregone conclusion.” Boy, was he wrong.

Instead of Big Brown becoming the 12th Triple Crown winner and first in 30 years, he was the first of 19 horses going for a Triple to finish last.

“He wasn’t himself,” the winning trainer, Nick Zito, said, referring to Big Brown. “Things happen for a reason.”

Da’ Tara and jockey Alan Garcia sprinted to the lead out of the gate. Big Brown, eager in the early going, ran up on Da’ Tara’s heels heading into the first turn — the first indication it wasn’t going to be his coronation day.

Da’ Tara had the lead down the backstretch, with Tale of Ekati in second, and Big Brown running third on the outside with a clear path. This was Big Brown’s moment, and Mr. Desormeaux asked him to go. He didn’t respond.

“He was empty. He didn’t have anything left,” Mr. Desormeaux said.

Da’ Tara opened up a clear lead turning for home, while Big Brown angled to the far outside under restraint. Big Brown still wanted to run, but Mr. Desormeaux knew it was over and focused on getting the colt home safely.

Big Brown was running on a quarter crack in his left front hoof that wasn’t patched until yesterday. Even as the horse was making his way to the starting gate, Mr. Dutrow said the crack was a “non-issue.”

“He looked fine,”, the on-call veterinarian, Dr. Larry Bramlage, said. “All I saw was when Desormeaux started to slow him down. The first thing you expected is something is wrong. He was not lame when he stopped here in front of the stands.”

Da’ Tara, the longest shot on the board, won by 5¼ lengths over Denis of Cork and covered the distance in 2:29.65. There was a dead heat for third between Anak Nakal and Ready’s Echo. Macho Again was fifth, followed by Tale of Ekati, Guadalcanal, Icabad Crane and Big Brown.

Da’ Tara paid $79, $28 and $14.80. Denis of Cork returned $5.80 and $4.10. Anak Nakal paid $7.60 and Ready’s Echo returned $6.20.

Mr. Zito spoiled a Triple Crown bid four years ago when he saddled Birdstone to an upset of Smarty Jones. He also trained Anak Nakal.

While the thousands of fans jammed along the rail focused on Big Brown, Da’ Tara pressed on to the finish line, obviously tired but triumphant.