updated 8:07 p.m. ET Jan. 29, 2007

KENNETT SQUARE, Pa. - So many people felt a stake in Barbaro’s recovery. They imagined his pain, grimaced each time he faltered, took heart as each day passed and he was still alive, making painfully slow progress.

The 2006 Kentucky Derby winner’s fight for survival was their fight, a symbol of strength, courage and comfort — and, more than anything else, a source of inspiration.

He was, after all, winner of the world’s most famous race, in a sport desperate for a superstar. For months he seemed, remarkably, to take everything that came at him: good and bad.

Finally, it was too much.

Barbaro was euthanized Monday after complications from his gruesome breakdown at last year’s Preakness, ending an eight-month ordeal that made him even more of a hero than he was as a champion on the track.

“Certainly, grief is the price we all pay for love,” co-owner Gretchen Jackson said.

A series of ailments — including laminitis in the left rear hoof, an abscess in the right rear hoof, as well as new laminitis in both front feet — proved too much for the gallant colt. Barbaro was given a heavy dose of a tranquilizer and an overdose of an anesthetic and put down at 10:30 a.m.

“I really didn’t think it was appropriate to continue treatment because the probability of getting better was so poor,” said Dr. Dean Richardson, chief of surgery at the New Bolton Center.

Richardson, fighting back tears, added: “Barbaro had many, many good days.”

NBC VIDEO Barbaro's battle ends Jan. 29: Kentucky Derby winner Barbaro was euthanized Monday after more complications arose from his leg injury suffered at the Preakness in May 2006. NBC's Dawn Fratangelo reports. Nightly News

The bay colt underwent nearly two dozen surgeries and other procedures, including cast changes under anesthesia. He spent time in a sling to ease pressure on his legs, had pins inserted and was fitted at the end with an external brace — extraordinary measures given that most horses never survive those injuries.

Weeks of positive reports turned into months. Barbaro was eyeing the mares, nickering, gobbling up his feed and trying to walk out of his stall. But Richardson warned there still could be trouble, and by mid-July, his greatest fear became reality — laminitis struck Barbaro’s left hind leg.

On Sunday, a day after Barbaro’s fight for survival had reached a critical point, Richardson compared the various injuries to a “house of cards.” One part falls, and the rest start to crumble.

In this case, it was the laminitis that attacked both front feet that left him vulnerable.

BARBARO LOSES LONG FIGHT Barbaro euthanized |   Images of his life Opinion: Barbaro's legacy will live on Horse racing community won't forget horse Siblings now must carry on legacy Owners unsure where to put ashes Cosmic Log: Could Barbaro be cloned? What they're saying about Barbaro's death   Discuss Barbaro | More on horse racing

“That left him with not a good leg to stand on,” Richardson said.

The disease affected his personality, too. The eyes that had been so bright and full of life were darker Monday morning. Barbaro clearly was in distress.

“You could see he was upset,” Richardson said. “That was the difference. It was more than we wanted to put him through.”

Roy and Gretchen Jackson were with Barbaro on Monday morning and made the decision in consultation with Richardson.

“We just reached a point where it was going to be difficult for him to go on without pain,” Roy Jackson said. “It was the right decision, it was the right thing to do. We said all along if there was a situation where it would become more difficult for him, then it would be time.”

With dark red roses on the table at an afternoon press conference, Richardson and the Jacksons were emotional talking about the colt. Many staffers welled up, and by early evening the lobby was overflowing with roses and other assorted flowers sent by grieving fans.

The scene seemed to mimic months earlier when Barbaro became America’s No. 1 patient after he first suffered his catastrophic injuries.

MORE FROM HORSE RACING

Horse racing Section Front

Skies open up, hamper Saratoga opener DRF: Da’ Tara out to stay hot all summer DRF: Turf filly Misty Ocean on a roll DRF: Five foreigners prep for Million Day DRF: Jenny Craig's husband, horse man dies Suspension cut for jockey who whipped horse in face Woodlands racetrack in Kansas closing next month Can horse racing thrive in the Motor City? Lava Man owners mulling potential retirement Latest horse racing videos Horse racing Section Front   Add Horse racing headlines to your news reader: