Nick Dougherty overcame an attack of the nerves to capture his second European Tour title in the £2.5million Alfred Dunhill Links Championship at St Andrews.
While Irish teenager Rory McIlroy all but clinched his tour card for next season in only his second event as a professional by finishing third, 25-year-old Dougherty closed with a one-under-par 71 for an 18-under aggregate of 270 and won the £392,368 first prize by two shots from compatriot Justin Rose.
Dougherty, who claimed his maiden title in the 2005 Caltex Masters in Singapore, had led by three strokes heading into the final day's play over the Old Course.
But the Liverpudlian saw that advantage swiftly disintegrate as he three-putted the first for a bogey and put his tee shot at the second into a bunker for another bogey.
Dougherty regained his composure and reeled off a trio of birdies from the fifth to keep his nose in front and, despite the menacing advances of Rose, McIlroy, Ernie Els and Paul Lawrie, held on to secure the biggest triumph of his career.
"This is a life-changing win for me but I felt very nervous at the start of the day," admitted Dougherty, who jumps to the top of the European Ryder Cup points table.
"I've been in this position before and it's not gone right but I spoke to my fitness coach, Ron Cuthbert, before going out and he told me to use the nerves as a positive thing.
"He said if I wasn't nervous it would be a bad thing and he told me to enjoy these moments. He was a real help.
"I got off to a pretty bad start but I trusted myself and my ability. I had some big players, like Ernie and Justin, chasing me but I got the job done. This is the win I've been after for two years and I'm very proud of myself."
Runner-up Rose, who closed the gap on Padraig Harrington in the race for the Order of Merit title after pocketing a consolation prize of £261, 577, saw his spirited challenge finally thwarted with a bogey at the 17th on his way to a 69.
McIlroy, the 18-year-old Ulster rookie, showed resilience and mental strength beyond his tender years to emerge from a turbulent spell on his inward half to post a battling 68 to clinch third place.
McIlroy, the former European Amateur champion, spilled a shot at the 12th before lashing his tee shot out of bounds at the 14th and racking up a double-bogey seven, but he responded in fine style and birdied the 15th, 17th and 18th to finish with a flourish and bank a cheque for £147,373.
He has now earned £157,924 from his two professional events and jumped to 110th on the money list and seems certain to become the youngest player - at 18 years and 156 days - to win his tour card in the shortest possible time.
Spaniard Sergio Garcia won his playing rights when he won his fourth professional event, the 1999 Irish Open, at the age of 19.
McIlroy said: "I knew at the start of the week I needed to do something pretty special to get my tour card and I am absolutely ecstatic."
England's Barry Lane mounted a final-day charge and fired a five-under 67 for a share of fourth with the 1999 Open champion Lawrie, whose bogey at the 17th on his way to a 71 handed McIlroy third place on his own.
Els had been making advances on Dougherty's lead having reached 17 under with three holes to play but a crippling triple-bogey seven at the 16th ended his hopes and he signed for a 71 which left him in a share of sixth with countryman Trevor Immelman.
Open champion Padraig Harrington, the Dunhill Links champion both last year and in 2002, could only muster a closing 73 and had to settle for a share of eighth.