Once again it was not to be for Padraig Harrington.

Second in the Players Championship in Florida last week, the 32-year-old Dubliner failed in his bid to win the BellSouth Classic in windy Atlanta after a real rollercoaster ride of a final round.

Four days before the start of the Masters world number eight Harrington finished fourth at Sugarloaf, his closing 72 containing an eagle and five birdies, but also three bogeys and two double bogeys.

The title went to American rookie Zach Johnson, who won only his 13th US Tour event by one from Australian Mark Hensby after a closing 72 that included almost as many thrills and spills.

Coasting four clear with eight to play the 28-year-old bogeyed four of the next five. But none of the chasing pack could take full advantage in the demanding conditions.

Three behind Johnson entering the day, Harrington three-putted the first two holes and then double-bogeyed the next. Four over for three holes and, with Johnson opening with a birdie, suddenly eight adrift.

After the long fourth, however, the gap was five, Harrington grabbing birdie while Johnson went in a creek and ran up a double bogey seven.

The Irishman then returned to the 418-yard fifth where he had taken seven in the third round - and this time it cost him a six after his approach went into sand over the green.

He was down to 12th place after that, but the thrills and spills continued when he holed out from 90 yards for an eagle three on the next.

Amazingly, he climbed all the way back to joint second spot with birdies at the eighth, 11th, 12th and 13th, but he still had four strokes to make up and, as with his pursuit of Adam Scott last week, it proved too much.

Johnson, ranked 126th in the world and winner of the "second division" Nationwide Tour last year, became the 14th different winner of 14 events on the circuit this season with a 13 under par total of 275.

That early double bogey was far from his only scare en route to victory. After avoiding a three-putt in his first 64 holes Johnson had two in a row to be only two ahead, but was back in command after a superb pitch to within inches of the cup on the 310-yard 13th.

He wobbled again with bogeys on the next two to be only one ahead of Hensby, but kept his nerve.

Harrington's hopes, meanwhile, were effectively ended when he missed the green at the short 16th and bogeyed.

One of only four sub-70 rounds all day came from England's Luke Donald, a 69 lifting him into a tie for eighth and earning him £75,000.

The 26-year-old former Walker Cup star from High Wycombe has now earned more this season - over £450,000 - than he did in the whole of 2003.

Disappointingly for Donald, who lost a play-off to John Daly in the Buick Invitational in California in February, he is not in the field for the Masters.

His performance, though, should boost his world ranking and take him closer to the world top 50 spot which will help him qualify for the year's other majors and World Championships.

And that could be key to whether he is eligible for the Ryder Cup in September. Donald, along with other US Tour-based players, will lose their European tour membership if they decide not to commit to 11 European events.

"I've given myself a lot more chances and been in contention a lot more this year," he said. "That was a good round in the conditions. I hit the ball pretty solidly and I'm happy with that."

Harrington said: "I just got four clubs wrong off the bat. It was very windy and very hard to judge, but I hit them in places that were really tough to get up and down from.

"It was difficult all through the round, but I was playing well and this has been a good week for Augusta without a doubt."

Collated final totals in the BellSouth Classic at TPC at Sugarloaf, Atlanta, Georgia, United States (USA unless stated, par 72):

(USA unless stated, par 72):

275 Zach Johnson 69 66 68 72 (£450,000 pounds)

276 Mark Hensby (Aus) 73 70 66 67 (£270,000)

277 Scott Hend (Aus) 72 66 68 71 (£170,000)

278 Padraig Harrington (Irl) 70 69 67 72 (£120,000)

280 Peter Lonard (Aus) 73 67 69 71 (£100,000)

281 Lee Janzen 75 67 68 71, Ben Crane 68 69 71 73

282 Luke Donald (Gbr) 72 70 71 69, Stewart Cink 75 67 69 71

283 Phil Mickelson 69 72 71 71

284 Grant Waite (Nzl) 73 72 70 69, Tim Petrovic 67 70 75 72, David Peoples 73 72 66 73, Brian Gay 68 70 69 77

285 Roger Tambellini 65 78 72 70, Steve Allan (Aus) 71 72 71 71, Tag Ridings 73 69 71 72, Neal Lancaster 70 75 66 74, Craig Bowden 66 71 72 76

286 Chris DiMarco 75 70 72 69, Chris Smith 70 70 74 72, Duffy Waldorf 73 70 71 72, Jeff Brehaut 71 74 69 72, Briny Baird 74 69 70 73, Arron Oberholser 72 68 71 75, Blaine McCallister 71 69 71 75, Glen Hnatiuk (Can) 70 72 68 76

287 Larry Mize 76 69 70 72, Kevin Na 73 71 69 74

288 Steve Stricker 69 76 73 70, Shaun Micheel 67 72 75 74, David Morland 72 70 72 74, Kris Cox 71 70 70 77, Steve Lowery 71 73 67 77

289 Rich Beem 69 75 73 72, Steve Elkington (Aus) 70 75 71 73, Harrison Frazar 71 74 69 75

290 Pat Perez 73 71 74 72, Robert Gamez 71 70 76 73, Franklin Langham 74 70 72 74, John Huston 70 73 72 75, Brent Geiberger 73 70 72 75, Steve Flesch 71 73 71 75, Joe Ogilvie 70 75 69 76

291 Brian Bateman 73 70 75 73, Brett Quigley 73 71 74 73, Bob Burns 76 69 73 73, Spike McRoy 70 73 74 74, Mike Weir (Can) 73 70 73 75, Jose Maria Olazabal (Spa) 65 77 73 76, Deane Pappas (Rsa) 72 72 71 76

292 Richard Johnson (Swe) 72 73 73 74, Carl Pettersson (Swe) 76 68 73 75, Chris Couch 72 69 75 76, Guy Boros 72 73 71 76

293 Rory Sabbatini (Rsa) 68 75 75 75, Billy Mayfair 68 76 73 76, Scott McCarron 74 71 72 76, Lucas Glover 75 70 72 76, Kevin Durkin 71 73 72 77, Jonathan Kaye 73 72 71 77, Dennis Paulson 72 73 71 77, Scott Simpson 68 76 70 79

294 Danny Briggs 70 74 75 75, David Branshaw 72 73 72 77

295 Bo Van Pelt 75 70 74 76, Brian Kortan 69 73 73 80

296 Roland Thatcher 72 71 72 81

297 Daniel Chopra (Swe) 71 73 76 77

298 Hirofumi Miyase (Jpn) 70 73 75 80

300 Brian Watts 71 73 77 79