Tony Johnstone, who almost quit the game in January, produced a brilliant final round to claim his sixth European Tour title in the Qatar Masters.
The 44-year-old carded a superb closing 70 at a windswept Doha Golf Club to beat overnight leader Robert Karlsson of Sweden into second place.
Johnstone, who is based in Sunningdale, birdied two of the last three holes for a 14-under-par total of 274 to claim the winner's cheque for £85,000.
New Zealand's Elliot Boult was two shots behind Karlsson in third with France's Olivier Edmond and Scotland's Dean Robertson joint fourth on nine under par.
David Higgins finished best of the Irish on six under-par 282 after a final round of 68 with Paul McGinley a shot further back on 283 after a disappointing two over par 74 in the final round. The tough conditions also took its toll on Eamonn Darcy and Des Smyth who finish on level par 286 after rounds of 77 and 76 respectively.
It was a remarkable turnaround in fortunes for Johnstone who despaired so much over the state of his putting just two months ago that he considered becoming "a window cleaner on very tall buildings!"
After the third round of the Dimension Data event in South Africa in January he told his wife that he had reached the end of his tether and would not play another tournament unless he cured his putting woes.
Step forward eye specialist Dr Ken West and coach Simon Holmes, the pair deciding that Johnstone was standing too close to the ball for a man with disproportionately long arms in a 5ft 8in frame, and the results speak for themselves.
"I said to my wife at the Dimension Data that's it - I was not going back to another tournament until I had sorted out how to putt," admitted the former Volvo PGA Champion.
"I'd been through the mill for six years and it finally got to the stage where my enjoyment of the game had been outweighed by the frustration.
"After the third round in Sun City I said that's enough and maybe it was a good thing. It gave me a jolt and got me going. I made some radical changes and it galvanised me and I'm absolutely loving it again."
Johnstone, trailing by one after the third round, got off to the perfect start, chipping in for an eagle on the first and then holing from 60 feet for par on the second to move into a one-shot lead over Karlsson, who was playing in the group behind.
The pair both bogeyed the fifth before Karlsson picked up a birdie at the ninth to get back on level terms and after another pair of dropped shots at the 14th, the decisive moment came when Johnstone birdied the 16th.
That restored his one-shot cushion and another birdie from 15 feet on the 18th effectively sealed victory, Karlsson narrowly missing his eagle chip to force a playoff and the following birdie attempt to finish two adrift.
"I was pretty happy with the way I played to be honest," Karlsson said. "I don't think I could have done much better."
Scotland's Paul Lawrie was far less happy after slumping to a final round 79, angrily damaging his putter on an ice box on the fifth tee after taking a double bogey six on the previous hole.
It meant the former Open champion - and 1999 Qatar Masters winner - had to use a variety of different clubs, from 3wood to pitching wedge on the green, as he dropped from joint sixth overnight to a tie for 27th.
A seven-shot lead shrunk to one, but Swede Sophie Gustafson was happy to take it as she beat Karrie Webb on her home turf and win the Women's Australian Open at Yarra Yarra, Melbourne yesterday.
Gustafson, who shaded Webb to win January's Subaru Memorial on the US LPGA Tour, overcame a stop-start round and the menacing presence of the world number one to extend her growing collection of national Open titles.
She finished 12-under par at 276, with rounds of 70, 69, 66 and 71 to collect $30,000 while Webb closed in with a final round 68, including birdies at the last two holes, to be one stroke adrift.
Australian veteran Jane Crafter, the 1997 winner, claimed outright third place at five under par.
