Charl Schwartzel raced into the clubhouse lead, joining China's Ashun Wu on nine-under-par with a 68 before the rain hit for the second successive day.
But he was one of just 32 golfers to complete their second rounds.
Luke Donald had only just begun his round after a disappointing 74 on day one, while first-round leader Kiradech Aphibarnrat had picked up two shots after six holes of his second round, to join Schwartzel and Wu on nine-under.
World number three Luke Donald partially recovered from his opening round of 74 and was even par after seven holes in the second round.
Three-times major winner Padraig Harrington, who opened his campaign with a strong 69, was one under through six holes on Friday.
South African Charl Schwartzel overcame extreme heat and a late lapse in concentration as he and China's Ashun Wu set the clubhouse target at nine under par with matching 68s.
Left stranded at four under after 11 holes following a similar weather-interruption on Thursday, Schwartzel returned to first complete an opening round of five-under 67 and followed it with a 68.
"I can't be too hard on myself because it's extraordinarily hot out there," said the 2011 Masters winner, who started from the 10th and was going six under for the day before dropping two shots in a row on the sixth and seventh.
"I lost a bit of concentration towards the end and made bad decisions on the sixth and seventh - poor club selections. I was in the middle of the fairway both times and made bogey. I hit a very poor shot on the seventh."
Playing on a sponsor's invitation, China's Wu completed the remaining six holes of his first round before joining Schwartzel on the clubhouse lead at the $2.75 million Asian Tour co-sanctioned event.
"I think it's important to play with a strategy in mind and choosing the right clubs will matter as well. I've been in a good form lately and I hope to maintain that," said Wu.