Open 2015: Zach Johnson triumphs in play-off at St Andrews

American Zach Johnson claimed his second major title with victory in a three-man play-off on a thrilling final day in the 144th Open Championship.

The 2007 Masters winner finished a shot ahead of South African Louis Oosthuizen and three ahead of Australian Marc Leishman over four extra holes.

Earlier, the three ended on 15 under to lead a competitive field at St Andrews.

Jordan Spieth's hopes of a Grand Slam were ended as he finished on 14 under along with Australia's Jason Day.

Joint halfway leader Danny Willett and fellow Englishman Justin Rose both carded two-under 70s, as did Spaniard Sergio Garcia, to finish joint sixth on 11 under.

American Jordan Niebrugge also hit a 70 to finish 11 under and claim the Silver Medal for leading amateur ahead of Ireland's Paul Dunne, the joint overnight leader, who shot a six-over 78 to drop to joint 30th on six under.

Australian Adam Scott was in contention but a poor back nine gave him a one-under 71 and a share of 10th on 10 under.

Ireland's Padraig Harrington, who claimed back-to-back Open titles in 2007 and 2008, started well with three birdies in his first five holes but a double-bogey on six checked his progress and he ended up carding a three-over 75 to finish joint 20th on seven under.

How the play-off was decided

Johnson struck just 15 putts over the first 12 holes of his final round on Monday to record seven birdies and his skill on the green again came to the fore in the play-off.

The 39-year-old holed challenging putts on the first and second to claim two birdies and go one shot clear of Oosthuizen and two ahead of Leishman.

Leishman, who had followed his stunning third-round 64 with a six-under 66 on Monday to head the leaderboard after making the cut by a shot, fell out of contention with two pars.

This left 2010 Open winner Oosthuizen, whose birdie on the last gave him a 69 and a shot at the Claret Jug, to challenge Johnson but after a bogey on the third extra hole he pushed his putt on the last just wide to give the American the win.

Spieth Slam hopes dashed

Masters and US Open winner Spieth started well in pursuit of a 2015 Grand Slam, birdieing three of the first seven, but a wayward tee shot and then a hugely over-hit putt on the par-three eighth ultimately led to a double bogey that looked to have cost him dear.

But such is the ability and cool temperament of the 21-year-old, he hit back with successive birdies on the ninth and 10th before sinking a 30-foot putt to join the clubhouse leaders on 15 under.

However, a bogey on the Road Hole 17th left him needing a birdie on the last - and when his chip rolled back off the green his hopes were left hanging on a putt that proved too much for the world number two. His three-under-par 69 was one shot shy of the play-off.

Jordan Spieth missed out on a third successive major title

The leading Brits

A run of four successive birdies from 11 to 14, helped Sheffield-born Willett to 11 under and joint sixth place, eclipsing his previous best Open finish - the tied 15th he managed at Muirfield in 2013.

Rose, the 2013 US Open champion, famously finished fourth as an amateur at Royal Birkdale in 1998 but his own 11-under overall score gives him his best finish in 12 Opens as a professional.

Fellow Englishmen Luke Donald (68) and Anthony Wall (70) both ended on nine under for a share of 12th, but it was a bad day for Scottish pair Paul Lawrie and Marc Warren, who carded 73 and 74 respectively to finish five under and tie for 40th.

The nearly men

Spaniard Garcia remains without a major title after claiming a 20th top-10 finish in one of golf's top four tournaments, courtesy of a round of 70 that began well but tailed away, with bogeys at 12, 13 and 17, to an 11-under finish.

It was another emotional finale for Jason Day, who was visibly upset after his par on the 18th left him one shot short of the play-off. His only consolation is an impressive ninth top-10 finish in his 19th major.

Australia's Jason Day has nine top-10 finishes in majors, including three second-place positions

American halfway leader Dustin Johnson continued his slide from the majestic to the mediocre, suffering a hangover from the three bogeys that ended his efforts on Sunday by dropping another three shots on the front nine to tumble further down the leaderboard.

A second successive three-over 75 left the US Open runner-up a disappointing four under overall and to reflect on another missed opportunity.

Amateur hour

Irishman Dunne, 22, was calmness personified on Sunday with a superb six-under 66 to take a share of the overnight lead but looked far less assured during Monday's final round, starting with a bogey as his professional rivals racked up birdies.

He hit three wayward tee shots on the par-four second before finally finding his first shot, which had come to rest on a green on an adjacent course. It was in bounds and playable but a second bogey followed.

Birdies at the third and fifth steadied him but a back nine comprising four bogeys and a double bogey saw him plummet to six under and fourth in the race for the Silver Medal.

That honour went to American Niebrugge, whose final-round 70 saw him finish two shots ahead of compatriot Oliver Schniederjans (67) and England's Ashley Chesters, who followed Sunday's 67 with a three-under 69.

"I would rank it the top accomplishment I've had so far: the Silver Medal in a major championship, especially at St Andrews, is definitely a dream come true," said Niebrugge, 21.

Early birdies

As in Sunday's third round, the course was there for the taking on Monday morning courtesy of calm, dry weather.

American Brendon Todd paved the way for what was possible in such conditions, going out at 09:40 BST to shoot a six-under 66 and establish an early nine-under clubhouse lead, matched soon after by England's Luke Donald and Germany's two-time major winner Martin Kaymer, who both carded 68.

Phil Mickelson was on course to better both but hammered his tee shot at the 17th way right and on to one of the balconies of the Old Course Hotel as part of a triple-bogey that ultimately led to a three-under 69 and the end of his prospects at seven under overall.