KENNETT SQUARE, Pa. — Barbaro underwent more than five hours of surgery yesterday to repair rear leg bones he'd broken in the Preakness, calmly awoke from anesthesia and "practically jogged back to his stall" for something to eat.

His survival, however, is still 50-50.

Despite the huge first step on the road to recovery, Dr. Dean Richardson said the Kentucky Derby winner's fate still came down to "a coin toss."

"Right now he's very happy," Richardson said after the surgery at the University of Pennsylvania's New Bolton Center for Large Animals. "He's eating, he's doing very good. But I've been doing this too long to know that day one is the end of things."

The strapping 3-year-old colt sustained "life-threatening injuries" Saturday when he broke bones above and below his right rear ankle at the start of the Preakness Stakes. His surgery began around 1 p.m. yesterday, and it wasn't until some eight hours later that Richardson and trainer Michael Matz emerged to announce the news.

"From the last time I saw him to now was a big relief," said a visibly fatigued Matz. "They did an excellent job. It's just an amazing thing to see him walk in like that.

"I feel much more comfortable now. I feel at least he has a chance."