Jorge Campillo of Spain and Dylan Frittelli of South Africa are the joint leaders after both shot 66s at Saujana Golf and Country Club for 15 under overall at the European Tour event.
"I had a few tough holes, but I managed to make the putts, so overall I played solid," Campillo said.
Henrik Stenson (73) and defending champion Fabrizio Zanotti (75) trail the leaders by 11 shots.
It was a day of low scores, with six golfers — including Campillo — making eagle on the par-5 first hole.
With 18 golfers separated by only three shots at the top, competition will be rife on Sunday.
Khalin Joshi of India and Berry Henson of the United States trail the leaders by one shot after matching 65s. Henson is a self-proclaimed "Mr. Sunday" after shooting 65 and 64 at the Singapore Open and Myanmar Open, respectively, and will be out for another low score.
Overnight leaders Phachara Khongwatmai (70) and Nino Bertasio (70) are 13 under, along with Prayad Marksaeng of Thailand (67), Japanese duo Hideto Tanihara (68) and Ryo Ishikawa (63) and Scotland's Marc Warren (69).
Westwood is one shot away from that pack in a group which includes New Zealander Ryan Fox, who holed out for an albatross on the first hole.
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