KUALA LUMPUR, March 22, 2013 (AFP) - Thailand's overnight leader Kiradech Aphibarnrat held a one-shot advantage at 10-under but still had nine holes remaining before play was halted for the day due to thunderstorms and failing light.
Meanwhile, world number three Luke Donald only managed to play seven holes at the Kuala Lumpur Golf and Country Club, finishing level on par after waiting almost the entire day to start his round.
He had birdies on the fourth and fifth holes, recovering slightly after carding a two-over 74 in first round.
Ireland's two-time Major winner Padraig Harrington, who shot a three-under 69 for his first round, faced a similar situation, playing just six holes Friday.
Schwartzel had to complete seven holes of his first round in the morning, finishing with a five-under 67.
But the 2011 Masters winner was back on the course half an hour later, reeling off six birdies before later dropping two shots to close the second round on 68.
That gave him a halfway total of nine-under par and a share of the clubhouse lead with Wu, who had also returned a 68 with five birdies and just one bogey.
"Overall I felt that I played well enough. It was really hot out there today," Schwartzel said.
China's Wu, playing in his second Maybank Malaysian Open, was happy with the lay of the course and that he was able to complete the second round.
"I like this golf course a lot. I think it's important to play with a strategy in mind this week and choosing of the right clubs to use will matter as well," Wu said.
Meanwhile, 19-year-old Gavin Green became the first Malaysian amateur in a decade to qualify for the weekend rounds after carding a two-day total of 141, three-under-par.
Leading scores on Friday after round two of the $2.75 million Maybank Malaysian Open at par-72 Kuala Lumpur Golf and Country Club.
135 - Charl Schwartzel (RSA) 67-68, Wu Ashun (CHN) 67-68
138 - Scott Jamieson (SCO) 66-72, Liang Wen-chong (TPE) 70-68, Lee Slattery (ENG) 68-70
139 - Prom Meesawat (THA) 68-71, Rafa Cabrera-Bello (ESP) 72-67, Pablo Larrazabal (ESP) 69-70, Joonas Granberg (FIN) 71-68, Alastair Forsyth (SCO) 69-70
140 - Bernd Wiesberger (AUT) 71-69, Matteo Manassero (ITA) 69-71, Raphael Jacquelin (FRA) 70-70, Jean-Baptiste Gonnet (FRA) 70-70
141 - Gavin Green (MAS) 73-68, Prayad Marksaeng (THA) 69-72, Jeev Milkha Singh (IND) 71-70, Ignacio Garrido (ESP) 70-71
142 - Alvaro Quiros (ESP) 75-67, Robert-Jan Derksen (NED) 72-70
143 - Mohd Siddikur (BAN) 71-72, Kim Gi-whan (KOR) 70-73, Alejandro Canizares (ESP) 72-71, Thitiphun Chuayprakong (THA) 72-71, Jorge Campillo (ESP) 73-70
144 - Richard Green (NZL) 74-70, Baek Seuk-hyun (KOR) 72-72, Scott Barr (AUS) 75-69, Johan Edfors (SWE) 76-68, Jbe Kruger (RSA) 73-71, Romain Wattel (FRA) 75-69
145 - Gaganjeet Bhullar (IND) 72-73, Joel Sjoholm (SWE) 74-71, Darren Beck (NZL) 72-73, Sukree Othman (MAS) 73-72, Rikard Karlberg (SWE) 72-73, Jyoti Randhawa (IND) 71-74, Daniel Chopra (SWE) 74-71, Lorenzo Gagli (ITA) 76-69