Rory McIlroy suffered more Honda Classic heartbreak as his dreams of landing the prize for a second time were shattered in a play-off.
Last year the Hollywood man walked off the same course half way through his second round citing toothache but this time he was confident of repeating his 2012 heroics.
But American Russell Henley came out on top at the first hole of a four-way play-off to deprive McIlroy of victory as the Honda Classic lived up to its name.
The pair, playing in the final group, both finished eight under alongside Ryan Palmer and Scotland's Russell Knox after a remarkable last hour at the Jack Nicklaus-designed PGA National in Palm Beach Gardens, Florida.
McIlroy had earned his place with a stunning approach to the last but faltered around the green when the hole was replayed for the play-off and it was Henley who prevailed with a birdie four.
Afterwards, McIlroy admitted he didn't deserve to finish top of the pile.
"I didn't play well enough to deserve to win today – if I had won I would have considered myself very fortunate," McIlroy admitted.
A jubilant Henley said: "This isn't going to sink in for a while.
"I was nervous coming down the stretch but I tried to enjoy every shot.
"The crowd was like nothing I have ever experienced before – I wish I could play in front of a crowd like that every day."
McIlroy began the day 12 under par, two clear of his playing partner, but both his birdies on the front nine were immediately cancelled out by bogeys.
He dropped another shot at the ninth to leave himself 11 under and it closed up further on the back nine.
McIlroy dropped another at the 12th and followed a double-bogey at 16 – where he hit out of a bunker into the water – with another bogey to fall out of the lead altogether.
Henley had pitched in at 14 for a second successive birdie but gave both strokes back at the next when he dunked his tee shot in the water.
Palmer bogeyed the last to fall to eight under and was joined by Knox, the Scot's double-bogey six at the 14th proving costly – but the pair were able to watch in hope while keeping loose for a possible play-off.
At the 18th, though, McIlroy produced a moment of magic to set up the chance of a fairytale winning eagle.
The 24-year-old's second shot carried the water and bunker in front of the green and stopped almost dead, 20 feet from the pin.
Henley responded by duffing his pitch on, leaving himself a 60-foot birdie putt which he lagged to within five.
McIlroy's eagle putt trickled just by on the right and after he tapped in, Henley also holed out to make the play-off and he kept his nerve to make birdie while his rivals fell away.
Earlier, world number one Tiger Woods withdrew after 12 holes of his final round due to back pain.
Woods shot 65 on Saturday to move into contention but was five over for his final round when he called it quits.
Woods' departure left his defence of the WGC-Cadillac Championship at Doral this week in doubt.
With the Masters only five weeks away, it would not be a surprise if Woods didn't line up in Miami, where he also met a premature end with knee trouble two years ago.
"It's my lower back with spasms," Woods said.
"It started this morning warming up. It's too early to tell about Doral. I'll have treatment every day and we will see about Thursday."
It was the sixth time Woods has been forced to withdraw through injury in 297 Tour starts.
Galgorm's Michael Hoey failed with a valiant attempt to reel in England's Ross Fisher at the Tshwane Open in South Africa. Hoey finished runner-up with a £113,000 consolation.
Trailing Fisher by five overnight, Hoey closed to within one shot of with a splendid display of controlled aggression on his opening 11 holes at Copperleaf Golf and Country Estate, an inspirational spell which yielded three birdies and an eagle at the 685-yard fourth.
However, the Belfast man's brave charge came to an abrupt halt on 12, where he carved a reckless approach shot into water on the right of the hole.
Fisher (33) then copper-fastened his fifth Tour win and first since the 2010 Irish Open at Killarney by holing from 24 feet for a golden eagle three at 15.