Sweden's Alexander Noren upstaged the big guns at the Maybank Malaysian Open on Thursday, enjoying a birdie spree for an eight-under-par 64 and a two-shot lead.

Noren mastered the tricky greens at the Kuala Lumpur Golf and Country Club to edge past early leader, Italian teen sensation Matteo Manassero who returned with a 66 in the US$2.5 million showpiece sanctioned by the Asian Tour and European Tour.

India's Jeev Milkha Singh, a two-time Asian Tour Order of Merit champion, Darren Beck of Australia, who has won once in the region, and Stephen Gallacher of Scotland returned matching 67s.

The tournament's top draws enjoyed mixed days. Young Irish star Rory McIlroy overcame his Masters Tournament hangover with a solid 69, despite not enjoying the benefit of a practice round. His score was matched by reigning British Open champion Louis Oosthuizen of South Africa.

World number one and PGA Championship winner Martin Kaymer of Germany, playing alongside McIlroy, fired a 70 while newly crowned Masters winner Charl Schwartzel of South Africa struggled with fatigue and jetlag to card a 73 in the 50th edition of Malaysia's national Open.

The best local performer was Malaysia's Ben Leong, who returned a 70 after surviving an injury scare last week while playing basketball.

The opening round was suspended at 7.05pm due to lightning with 12 players to resume their rounds at 8.30am, Friday.

Noren, whose lone European Tour victory was the 2009 Omega European Masters, overcame some early jitters with five birdies and a bogey for an outward 32 which he matched coming home with four more birdies.

"I was really nervous going into this round. I don't know why. I'm normally nervous after a little break. I had two weeks off and I worked hard on my game these two weeks," said the 28-year-old, who credited his putter for the hot start.

Manassero, who became Europe's youngest winner at 17 years and 188 days last season when he won the Castello Masters in Spain, set the early target in his morning round. He turned in 31 which included four straight birdies from the 15th hole and added two more birdies and a bogey in his homeward nine.

"Those four in a row were really good. They got me going from one-under to five-under straight away. It was a good push and I felt as if I had to keep going on the back nine," said the dashing Italian, last year's rookie of the year in Europe.

He will celebrate his 18th birthday next Tuesday and hopes to have the Seagram Trophy, which is awarded to the Maybank Malaysian Open winner, as an early gift. "It would be a nice way to celebrate my birthday," smiled the Italian.

Singh, who is 22 years older than flight mate Manassero, birdied the last hole to stay in touch with the leader. Having struggled with injuries since last year, Singh said he was about 60% back to his best form which saw him win the Asian Tour Order of Merit titles in 2006 and 2008.

"We pushed each other. He (Manassero) is a great player and has a lot of fire in him. He's got the whole package. But I'm pleased with how I hit the ball and had good distance control with the irons."

McIlroy, who led for 63 holes at the Masters before tumbling with a disappointing final round 80, credited his caddie JP Fitzgerald for guiding him around the challenging course.

"From not seeing the course, three under is a good score. JP did a great job," said the Irishman, the world number nine. "What happened last week is completely behind me now. There are more people upset about that round than I am. It's one bad round. I'll live and I'm getting on with it."

Kaymer failed to cope with the putting surfaces as he burned the edges of the cup on numerous occasions. "I was playing good golf. Obviously it is very difficult to make putts here. There's a lot of grain. I gave myself a lot of chances so if I keep playing like this, maybe one of these days I will drop a few putts," said the German.

The dash halfway around the world to keep his commitment with the Maybank Malaysian Open seemed to have taken its toll on Schwartzel, who won the Masters with four closing birdies last weekend. Struggling in the notorious Malaysian heat, he stumbled to an opening 39 but fought back with two birdies.

"I felt uncomfortable and the swing wasn't nearly as it good as it was. Not feeling good right now. I'm struggling to focus," said the slender South African.

"The body isn't responding right now but it will come. Only good thing is that I didn't put myself way out of it. I came back on the back nine, made two under which is moving in the right direction. A couple more of those under par and maybe by the 72nd hole, I'll be close."

Leading first round scores

64 - Alexander NOREN (SWE).

66 - Matteo MANASSERO (ITA).

67 - Jeev Milkha SINGH (IND), Darren BECK (AUS), Stephen GALLACHER (SCO).

68 - Jamie DONALDSON (WAL), SIDDIKUR (BAN).

69 - Marcus FRASER (AUS), Chris RODGERS (ENG), Louis OOSTHUIZEN (RSA), Chawalit PLAPHOL (THA), Scott BARR (AUS), Daniel GAUNT (AUS), Kwanchai TANNIN (THA), Rory MCILROY (NIR), James MORRISON (ENG), David DRYSDALE (SCO), Alejandro CANIZARES (ESP), Brett RUMFORD (AUS).

70 – LIANG Wen-chong (CHN), LIN Wen-tang (TPE), Ben LEONG (MAS), BAEK Seuk-hyun (KOR), Jason KNUTZON (USA), Robert ROCK (ENG), Martin KAYMER (GER), Soren HANSEN (DEN), Simon DYSON (ENG), CHAN Yih-shin (TPE), Nicolas COLSAERTS (BEL), Peter LAWRIE (IRL), Pablo LARRAZABAL (ESP).