Phil Mickelson - 2013 Open Champion (Getty Images)
Five weeks after suffering the heartache of a record sixth runner-up finish in the US Open Championship, Phil Mickelson won The 142nd Open Championship at Muirfield in thrilling fashion.
Starting the day five shots behind home favourite Lee Westwood, Mickelson surged through a crowded leaderboard with a stunning five under 66, equalling the lowest round of the week.
The 43 year old finished three under par and the only man in red figures, three shots clear of Sweden's Henrik Stenson, with overnight leader Westwood a shot further back in third alongside compatriot Ian Poulter and Masters Tournament champion Adam Scott.
World Number One Tiger Woods, chasing a 15th Major title and first since 2008, began the day two off the lead but was never a factor after three early bogeys and finished in a tie for sixth after a round of 74.
Mickelson is now three quarters of the way to the career Grand Slam after previous wins in the Masters Tournament and US PGA Championship, and could easily have completed it here given the events of last month.
He had celebrated his 43rd birthday by taking a one shot lead into the final round of the US Open at Merion, only to card a closing 74 and lose out to Justin Rose.
The left-hander's fifth Major title came just seven days after he won the Aberdeen Asset Management Scottish Open at Castle Stuart Golf Links, after which he rated the prospect of lifting the Claret Jug as "the biggest accomplishment of my career if I were able to do it".
Having done just that thanks to four birdies in the last six holes and the lowest final round of his Major career, he said: "I'm playing some of the best golf of my career. It's the best I've ever putted. Today will be one of the most memorable rounds of golf I've ever played.
"It's probably the greatest and most difficult win of my career. It is great to be part of any Open Championship and to win at Muirfield feels amazing."
Previous Open winners at Muirfield include Gary Player, Jack Nicklaus, Lee Trevino, Tom Watson, Sir Nick Faldo and Ernie Els.
Mickelson said: "The range of emotions I feel are as far apart as possible in the last month after such a tough loss. You have to be resilient in this game and take losses and use them as motivation to work harder and come back stronger."
Mickelson's triumph meant more heartache for Westwood, who took a two shot lead into the final round as he sought his first Major title at the 62nd attempt.
The 40 year old, aiming to become the first English winner of The Open since Faldo in 1992, briefly led by three shots after a birdie at the fifth, but that would be his last birdie of the day in a round of 75.
"Phil must have played really well. Five under was a good round of golf this afternoon," Westwood said.
"You birdie four of the last six round here any day is good going, but to do it today in the last round of a major is an even better finish."
After a dropped shot on the third, Westwood recovered his composure with a superb three iron from more than 200 yards into the green on the fifth after finding sand off the tee.
Converting the birdie putt from 12 feet briefly gave Westwood the luxury of a three shot lead, but Stenson reduced the gap with a birdie on the ninth and Westwood soon found trouble on the seventh.
His first attempt to escape from a greenside bunker failed, but the ball fortunately just avoided rolling back into one of his footprints and from there he splashed out to 12 feet and salvaged a bogey with another excellent putt.
Scott had looked to be fading out of contention as he stood two over through six holes, but the Australian suddenly came to life with four birdies in five holes from the seventh, and when Westwood bogeyed the eighth after another visit to the sand, there was a three-way tie at the top between Scott, Westwood and Stenson.
Stenson's challenge faltered with back-to-back bogeys on the 12th and 13th, but almost unnoticed Mickelson had moved through the field into contention thanks to a flawless front nine of 34 and, after a dropped shot on the tenth, birdies on the 13th and 14th.
When Scott bogeyed the 13th, Mickelson was into a share of the lead. When Westwood did likewise minutes later and Scott three-putted the 14th, Mickelson was out in front.
Finding the green in two on the par five 17th - two massive hits into the wind on the 575 yard hole - set up the simplest of two-putt birdies, but Mickelson was not finished yet.
His approach to the 18th flirted with a greenside bunker but rolled perfectly round behind the hole to leave a birdie putt from 12 feet that never looked like missing, and for the second week in succession he was able to hug his wife Amy and children Evan, Amanda and Sophia in celebration.