US Masters runner-up Louis Oosthuizen showed no ill-effects of his play-off heartbreak and long-haul trek to Southeast Asia to fire an opening six-under 66 at the Malaysian Open.

The South African, who lost out to American Bubba Watson in Augusta on Sunday, was tied for third alongside American Jason Knutzon and India's Jyoti Randhawa at the European and Asian Tour co-sanctionned event in Kuala Lumpur.

Oosthuizen's compatriot and close friend Charl Schwartzel finished the day in front after a 64 left him one clear of India's Jeev Milkha Singh.

The South African duo looked refreshed ahead of their early tee time and they clearly enjoyed each other's company as they laughed and joked in the cool, morning temperatures.

"I feel like I'm swinging it well and I think a lot of times I'm used to a lot of travel so you adapt quickly," 2010 British Open champion Oosthuizen said.

There were two Irish involved with Peter Lawrie finishing one over after a 73, while Michael Hoey finished on six over after a 78.

Oosthuizen, also grouped with Thailand's Thongchai Jaidee (73), received the loudest cheer from the small galleries that woke early to see how he would react to the agony of missing out in the year's first major.

After pulling his drive slightly left on the 10th, his first hole, he munched on an apple before hitting a fairway wood to the edge of the uphill green and he then got up and down for a birdie four.

A good tee shot at the 226-yard 11th set up a nine-foot birdie putt that the South African rolled in to give him a dream start and a second two came at the 15th when he rifled his 199-yard first stroke next to the pin.

The highlight, though, was an eagle three at the third.

"I hit a three-iron in there and I made a nice long putt," Oosthuizen said. "I thought I would struggle a bit more on the greens speed-wise but I felt comfortable and I made quite a few putts."

The only negatives for the 29-year-old world number 19 were dropped shots at the par-four first and sixth but they were offset by birdies at the fourth, fifth and seventh.

"I felt good ... I made two stupid bogeys but yeah it was still good. I had a good night's rest and I'll try for the next 24 hours to hopefully have a lot of rest," four-times European Tour winner Oosthuizen said.

Schwartzel, the 2011 U.S. Masters champion who finished 11th here last year, produced nine birdies at the $2.5 million event in Malaysia as he attempts to win for the first time since his Augusta triumph.

"I have worked hard at my game for the last couple of months and haven't had anything happen for me. But it has been feeling good for a long time and today I seemed to put it together, eight-under is a good score for me," he said.

World number seven Martin Kaymer of Germany had five birdies, two double bogeys, one bogey and an eagle in an eventful 70, a score matched by defending champion Matteo Manassero of Italy.