Scott collected 11 birdies during a magnificent round
FINAL ROUND LEADERBOARD
(GB & Ire unless stated):
-20 A Scott (Aus)
-17 H Stenson (Swe)
-15 C Schwartzel (SA
-14 J Edfors (Swe)
-13 L Westwood
-11 C Montgomerie
-10 N Dougherty, S Garcia (Sp),
Australia's Adam Scott produced a dazzling 11-under-par 61 to win the Qatar Masters for the second time.
Scott, who began three behind overnight leader Johan Edfors, birdied the first five holes and never looked back.
The 2002 champion opted for safety at the last where a par-five left him 20 under for a sixth European Tour title.
Henrik Stenson (65) was runner-up on 17 under, with England's Lee Westwood (65) fifth on 13 under and Scot Colin Montgomerie (69) one shot further back.
It was a good week for both the Britons, but neither they nor anyone else was able to live with Scott whose opening four-three-two-three-three burst helped him reach the turn in 30 shots.
A hat-trick of birdies from the 10th tightened his grip on the tournament and raised the prospect of him equalling the European Tour record for the lowest final round by a winner.
The 27-year-old needed to birdie the last to match Jamie Spence's 12-under-par 60 at the 1992 European Masters.
Henrik did everything right - he deserved to win the tournament
But he chose to lay up short of the water and sand guarding the front of the green and had to settle for a par after his pitch was off-line.
Sweden's Edfors ended fourth after a 70, while Stenson, the 2006 champion, had to settle for a second runner-up spot in the event after starting the day in third place. Sergio Garcia (67) tied for seventh with six others.
"Stringing off five in a row and then to keep it going was good. It put pressure on the others," said Scott. "Henrik did everything right. He deserved to win the tournament. It's hard for the guys who were leading."
Scott was the world number eight at the start of the week, but will move up three places on Monday when the new rankings are announced.