John Daly, a two-time major winner, continued to play Saturday, just a few days after his mother's death. He shot a third-round, 2-under-par 70 and is tied for 30th at minus-2.
Lafeber, who opened the third round with a four-shot lead, had it on cruise control Saturday with a pair of birdies at two and three. He dropped a shot at the fourth but reclaimed the lost stroke with a birdie at seven. Lafeber dropped another shot at nine but was still in command, extending his lead at one point to five shots.
Harrington failed to make a move because of spotty play on the front nine. He bogeyed the fourth when he went into water, three-putted the sixth for par and three-putted the ninth for a bogey.
Lafeber birdied 11 to stay well ahead but never got anything going on the back nine after that birdie. He parred the next five holes before a bogey at 17, a hole he birdied the previous two days. Lafeber's lack of birdies on the back nine left the door open for Harrington and Immelman.
Harrington, who finished second on the Order of Merit race for the second consecutive year in 2002, mounted his charge on the second nine with a birdie at No. 10. He birdied 14 and 15 after making solid par saves at the 12th and 13th holes.
'I played quite nicely through the back nine. There were a couple of wayward shots that were recovered,' said Harrington, who shot a 4-under 68 on Saturday. 'Sometimes it's nice when you miss a few greens and you're getting it up and down because when you get your birdie chances, you also take them and get them in.'
Immelman, who recorded a pair of runner-up finishes in 2002, collected back-to-back birdies three times on Saturday, including birdies at 14 and 15 to polish of his round of 68.
American Andrew Pitts is alone in fourth place at 10-under par, followed by Ian Woosnam and Thongchai Jaidee, who share fifth place at 8-under-par 208.
For Woosnam, who served as Sam Torrance's vice-captain at The Ryder Cup in September, his 4-under-par 68 puts him in a position for his first official victory on the European Tour since the 1997 Volvo PGA Championship.
'If I'm five behind, I still have a chance to win because I think this is the sort of course that I think you can score low on if you play really well,' Woosnam said. 'I think the pin positions could get even trickier tomorrow.'
Soren Hansen (70), James Kingston (71), Henrik Nystrom (67) and Simon Yates (71) share seventh place at 7-under-par 203.
Jarmo Sandelin, the 2001 Asian Open champion, is part of a group at 5-under par, while Torrance is a shot further back at minus-4.
This event kicks off the 2003 European Tour schedule and is co-sanctioned by the European Tour and the Asian PGA Tour or Davidoff Tour.
Full-field scores from BMW Asian Open