Thomas Bjorn fired a 5-under 66 on Thursday to grab the first-round lead at the Singapore Open, which was suspended due to lightning.

Half of the 156-player field, including world No. 1 and Race to Dubai leader Rory McIlroy, will conclude first-round play Friday.

The current leaderboard is dominated by those who wrapped up their opening rounds before lightning forced golfers into the clubhouse.

Chinnarat Phadungsil, Pablo Martin and Simon Khan all shot 67 at the Serapong Course at Sentosa Golf Club to share second place.

Paul Casey, Y.E. Yang and Kwanchai Tannin are currently in third at 3-under, as is Chapchai Nirat, who has completed just five holes.

This event was also hampered by poor weather last year, when Gonzalo Fernandez-Castano bested Juvic Pagunsan in a playoff on a Monday after play was reduced to 54 holes.

McIlroy is currently at even par through eight holes. He had just sent his tee shot into the rough on No. 9 when play was halted.

Four-time major champion Phil Mickelson completed his round at 2-over 73. The lefty was hampered by a double-bogey, bogey, bogey stretch which began on the par-3 14th.

World No. 6 Adam Scott, a three-time winner at this event, finished at even par, while No. 10 Louis Oosthuizen is 2-up through eight holes.

"I did not play very well on the front nine (after starting at the 10th) and a bit better on the back nine," said Scott. "I was not hitting it very close and was not making many of the (birdie) putts. It was hard work actually getting round in even par."

Bjorn, who is still searching for his first victory of the season after recording three European Tour wins in 2011, carded five birdies, with his only stumble coming in the form of a bogey on No. 3. He recovered from that misstep with back-to-back birdies starting on No. 4.

"I came here and saw the golf course and it's set up to be tricky this year and I knew that everything was about driving the golf ball well," said Bjorn. "It is not the longest golf course in the world so if you can keep it in the fairway you can produce a score and I did that very well today."

NOTES: Bjorn finished 66th at this event last year after missing the cut in both 2009 and 2010 ... Scott won this tournament in 2005, 2006 and 2010 ... McIlroy has finished in the top 10 in six of his last seven events, including three wins ... Mickelson finished tied for second last week at the WGC-HSBC Champions.