The Englishman shot a 6-under 66 to finish at 23-under 265 at the Oceanico Victoria and move to the top of the European tour money list. Molinari had a 70 and Padraig Harrington had a 67 to finish third another two shots back.

Westwood, who had a bogey-free round, nearly pitched in at No. 17 before sinking his birdie to gain a two-shot lead when his Italian rival bogeyed the par-3 16th.

"It was nice to finish it off, (because) you never know when the next win is going to come and you start to question yourself," said Westwood, who lost three playoffs and had 26 top-10 finishes since a British Masters triumph in September 2007. "Winning is definitely a habit and I got out of the habit. Hopefully, now (that) I have won again I can win more."

Overnight leader Retief Goosen slumped to a 75 that left the two-time U.S. Open champion tied for sixth place six back of Westwood.

Harrington bounced back from a third-round 71 that the Irishman blamed on dehydration.

"I struggled to concentrate. I drank a phenomenal amount, just not enough," he said. "My trainer was watching on TV and you can see it in your face _ your eyes really."

Westwood bumped teenage golfer Rory McIlroy, who shot a 66 to finish tied for 30th at 12 under, into second in the standings for the Race to Dubai, which has replaced the European Order of Merit title.

"You always slightly doubt yourself in the back of your mind and to be No. 1 again feels great," Westwood said. "I'm also delighted about the world rankings. I always have a good look at that and it's a reflection of my consistency."

(This version CORRECTS SUBS lede to correct to Sunday.)