KUALA LUMPUR, April 17, 2014 (AFP) - Big-hitting Nicolas Colsaerts of Belgium was just a stroke back on 66 after matching the Englishman's birdie count but falling short due to a pair of bogeys on day one at the Kuala Lumpur Golf and Country Club.
Westwood, who managed a seventh-place finish at the Masters on Sunday, stumbled out of the blocks in Malaysia with a bogey on his first hole of the day.
But he kept a clean card the rest of the way by sinking some long putts and ending the day with three straight birdies.
"Yes, I played well. I didn't start off well, bogeying the par-five 10th, but fortunately that didn't set the tone for the day," he said. "I hit it really well and hit it close a lot.
"I played well last week, and am happy to carry that on today. It's nice to have a good start and build some momentum for the week," said Westwood, who won the Malaysian Open in 1997.
Michael Hoey of Northern Ireland and Ricardo Santos of Portugal were two shots back of Westwood at the $2.75 million event, jointly sanctioned by the Asian Tour and European Tour.
Former British Open champion Louis Oosthuizen of South Africa had a steady round but ended the day seven shots back on even-par 72, with his two birdies cancelled out by a pair of bogeys.
Most golfers completed the round, but a rain delay of about an hour meant that a number were still on the course with several holes to go when play was called due to fading light. They will finish their first rounds early Friday.
Defending champion Kiradech Aphibarnrat got out to an even slower start than Westwood, with a bogey and double bogey on the front nine.
But the burly young Thai, last year's Asian Tour Order of Merit winner, clawed his way back to a one-under 71 thanks to three birdies in the last six holes.
Kiradech said the weather delay gave him a chance to settle down and smooth out his tempo.
"I have to thank the evening rain for playing a part in my improvement on the back nine," he said.
His compatriot Thongchai Jaidee also struggled early with three bogeys on his first six holes. But the tournament's two-time champion righted the ship with six birdies the rest of the way to close at even-par 72 and keep Westwood in sight.
Leading first-round scores on Thursday in the $2.75 million Maybank Malaysian Open at the Kuala Lumpur Golf and Country Club:
65 - Lee Westwood (ENG)
66 - Nicolas Colsaerts (BEL)
67 - Michael Hoey (NIR), Ricardo Santos (POR)
68 - Jbe Kruger (RSA), Julien Quesne (FRA)
69 - Edoardo Molinari (ITA), Richard T. Lee (CAN), Prayad Marksaeng (THA), Soren Hansen (DEN), Bernd Wiesberger (AUT), Eduardo de la Riva (ESP), Craig Lee (SCO), Thaworn Wiratchant (THA)
70 - Prom Meesawat (THA), Bryce Easton (RSA), Scott Hend (AUS), Baek Seuk-hyun (KOR), Tommy Fleetwood (ENG), Raphael Jacquelin (FRA), Wade Ormbsy (AUS), Arnond Vongvanij (THA), Antonio Lascuna (PHI)
71 - Elmer Salvador (PHI), Francesco Molinari (ITA), S.S.P. Chowrasia (IND), Marco Crespi (ITA), Anthony Kang (USA), Garth Mulroy (RSA), Kiradech Aphibarnrat (THA), Matteo Manassero (ITA)