Aphibarnrat was 3-under, including a birdie at the par-4 ninth, through nine holes of his second round when play was suspended because of darkness. He's 10-under for 27 holes.
Rain Thursday and Friday backed up play and some golfers are yet to begin their second rounds. Play is to resume at 7:45 a.m. Saturday in Kuala Lumpur.
Charl Schwartzel and Wu Ashun each completed the second round in 4-under-par 68 and are tied for second at 9-under 135. Edoardo Molinari, 2-under through five second-round holes, is at 8-under for the tournament and is in fourth place.
Schwartzel was 4-under through 11 holes Thursday when play was stopped and he had to complete that round Friday before beginning his second round. He was 6-under through 14 holes in the second round but suffered back-to-back bogeys and fell back.
Wu had a final-hole birdie in his second round in pulling even with Schwartzel.
Aphibarnrat posted back-to-back birdies at Nos. 3 and 4 before his ninth-hole birdie pushed him clear of Schwartzel and Wu.