Westwood was in a class by himself last year, seizing the title at the Kuala Lumpur Golf and Country Club by seven strokes and adding to a previous win in the tournament way back in 1997.
"I am always comfortable playing in Malaysia, and with last year’s win one of my best ever, I am ready to defend my title on a course where I almost feel like a member," said Westwood, 41.
Few non-Asian players can rival the former world number one's record in the region.
Westwood has 42 pro victories in his career including seven in Asian Tour-sanctioned events and several others in the region.
His most recent Asian Tour win came in the Thailand Golf Championship in December, the second time he won that event.
The US$3 million Maybank Malaysian Open starting on Thursday is co-sanctioned by the European and Asian Tours.
Since his victory last year in Kuala Lumpur, Westwood has struggled to remain in top form and is now ranked 30th in the world.
But, following his one-shot victory in Thailand in December, he finished a solid ninth place last week in the Dubai Desert Classic, won by world number one Rory McIlroy.
Besides a challenging course that puts a premium on accuracy, competitors typically must contend with hot and steamy local conditions that can sap the resolve of the un-acclimated, while frequent rain and lightning delays can disrupt momentum.
But the tournament, held last year in April, is being staged earlier this year, and recent weather conditions have been relatively balmy.
Two Thai players in the field who know how to handle Malaysian conditions are ThongchaiJaidee, who has won the event twice before, and Kiradech Aphibarnrat, who took the title in 2013.
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