DUBAI, Feb 3, 2013 (AFP) - On a difficult day at the Majlis course of Emirates Golf Club, Gallacher battled it out gamely against South Africa's Richard Sterne before the magic second shot with a sandwedge from 115 yard changed the complexion of the tournament.
It was Gallacher's fifth eagle of the tournament and it helped him close the tournament with a one-under par 71 round.
That gave him a four-day tally of 22-under par 266, matching the all-time lowest winning total in the history of the tournament (Thomas Bjorn in 2001).
The victory was only the second European Tour win for the 38-year-old Scotsman. His last win came way back in October 2004 when he won the Dunhill Links Championship.
Sterne (71) had a back nine wobble and was second at 19-under par 269, while Chile's Felipe Aguilar (69) and Denmark's Thorbjorn Olesen (71) were tied third at 17-under par 271.
World No8 Lee Westwood (68) of England looked good to create some drama, but after reaching 17-under par with four holes to play, he missed a birdie chance from five feet and made two bogeys and a birdie to finish tied fifth at 272 alongside Australian Marcus Fraser (67).
"I knew it was going to be a difficult day given the gusty wind and I knew I just had to stay patient throughout. Anything could have happened out there if you caught a bit of wind," said Gallacher, who is expected to rise to No60 in the world from his present ranking of 111.
"I didn't realise it is 201 tournaments since my last win, but now that I have got it, it is even sweeter."
It was a tentative beginning from Gallacher, who lost his three-shot lead in the second hole itself after missing a four-footer par putt on the first and pushing his tee shot into the trees right of the short par-4 second green.
Sterne, on the other hand, chipped it to two feet for his first birdie of the day on the second.
Both players made birdies on the par-5 third hole and were tied at 20-under par.
Sterne made the turn after six consecutive pars, while Gallacher kept mixing brilliance with the mediocre. On the eight hole, he made a bogey after hitting his tee shot into the waste area, and then hit a stunning second shot to three feet from the rough and in between the trees to an unsighted pin for a birdie on the ninth.
Sterne edged ahead with a birdie on the par-5 10th, but Gallacher limited the damage with a par putt from 20 feet.
One ahead after 10, Sterne then dropped shots on consecutive holes to hand over the lead once again to Gallacher, only to tie again on the par-5 13th when he birdied the hole and his rival made a par.
The key moment, obviously, was his eagle on the 16th, coupled with another brace of dropped shots on the 15th and 16th from Sterne.
The win is almost certain to qualify Gallacher for the WGC-Accenture Match Play Championship, and put him in a good position to get into the top-50 of the world and a first start at the Masters in April.
"That would be something. The Masters is the only Major that I haven't played and have always watched it on TV. But this win certainly changes my schedule a wee bit and I am very happy about that," added Gallacher.
England's Robert Rock, winner of last year's Abu Dhabi HSBC Championship, showed glimpses of his old form when he shot a 68 and moved into a tie for seventh place at 15-under par along with Portugal's Ricardo Santos and England's Steve Webster.
Final round scores in the $2.5million Omega Dubai Desert Classic on Sunday at the par-72 Majlis course of Emirates Golf Club:
266 - Stephen Gallacher (SCO) 63-70-62-71
269 - Richard Sterne (RSA) 62-70-66-71
271 - Felipe Aguilar (CHI) 68-68-66-69, Thorbjorn Olesen (DEN) 67-66-67-71
272 - Marcus Fraser (AUS) 67-69-69-67, Lee Westwood (ENG) 67-71-66-68,
273 - Ricardo Santos (POR) 66-71-69-67, Robert Rock (ENG) 70-68-67-68, Steve Webster (ENG) 69-69-65-70,
274 - Jeev Milkha Singh (IND) 68-67-67-72, Tommy Fleetwood (ENG) 65-68-69-72
275 - Matteo Manassero (ITA) 66-71-70-68, Andy Sullivan (ENG) 69-67-69-70, Gareth Maybin (NIR) 69-67-69-70,
276 - Lorenzo Gagli (ITA) 68-71-69-68, Garth Mulroy (RSA) 71-70-66-69,
277 - Marc Warren (SCO) 67-72-71-67, Jose Maria Olazabal (ESP) 70-67-71-69, Ignacio Garrido (ESP) 69-68-70-70, Peter Lawrie (IRE) 66-70-71-70, Rafael Cabrera-Bello (ESP) 69-69-69-70, Sergio Garcia (ESP) 68-67-71-71, Fredrik Andersson-Hed (SWE) 67-71-68-71, Andreas Harto (DEN) 67-67-71-72, Maximilian Kieffer (GER) 66-68-69-74
278 - Henrik Stenson (SWE) 69-69-71-69, Scott Jamieson (SCO) 65-72-70-71, Noh Seung-Yul (KOR) 66-72-67-73, Justin Walters (RSA) 68-70-67-73,
279 - Ricardo Gozalez (ARG) 71-70-69-69, Chris Wood (ENG) 68-68-74-69, David Howell (ENG) 70-68-72-69, Robert-Jan Derksen (NED) 68-72-69-70, Anthony Wall (ENG) 68-72-68-71, Raphael Jacquelin (FRA) 70-68-68-73, Alexander Noren (SWE) 68-71-67-73,
280 - Robert Coles (ENG) 73-68-70-69, Craig Lee (SCO) 69-70-71-70, Paul Casey (ENG) 66-70-73-71, Gary Lockerbie (ENG) 68-70-71-71, Gregory Bourdy (FRA) 67-71-71-71, Gregory Havret (FRA) 70-67-72-71, Lee Slattery (ENG) 69-70-70-71, Marcel Siem (GER) 68-72-68-72, Jamie Donaldson (WAL) 67-73-68-72,
281 - SSP Chowrasia (IND) 69-70-74-68, Simon Khan (ENG) 68-73-70-70, David Drysdale (SCO) 69-70-69-73
282 - Marten Lafeber (NED) 69-71-71-71, Pablo Larrazabal (ESP) 71-70-71-70, Jorge Campillo (ESP) 69-71-69-73,
283 - Simon Dyson (ENG) 70-71-73-69, Alessandro Tadini (ITA) 70-71-71-71, Matthew Nixon (ENG) 69-69-73-72, Mikko Ilonen (FIN) 71-70-69-73, Romain Wattel (FRA) 68-67-71-77, Chris Doak (SCO) 65-69-71-78, Jbe Kruger (RSA) 70-66-69-78,
284 - Tom Lewis (ENG) 69-72-74-69, Mark O'Meara (USA) 67-74-71-72, Bernd Wiesberger (AUT) 71-68-73-72, David Horsey (ENG) 75-66-70-73, Todd Hamilton (USA) 70-68-70-76
285 - Damien McGrane (IRE) 68-72-73-72, Jean-Baptise Gonnet (FRA) 72-68-73-72, Thongchai Jaidee (THA) 68-68-73-76
287 - Oliver Fisher (ENG) 69-72-73-73
288 - Thomas Levet (FRA) 68-70-77-73, Keith Horne (RSA) 68-71-74-75, Eddie Pepperell (ENG) 68-70-72-78
290 - Jaco van Zyl (RSA) 69-71-73-77