Sandelin, who started one behind third-round leaders Carl Pettersson and Miguel Angel Jimenez, slipped two shots off the pace with an opening bogey. He quickly rebounded with four birdies over the next five holes to take over the top spot at 9-under-par, and he was soon joined there when Jimenez notched his second birdie of the day at the sixth.
A birdie just before the turn lifted Sandelin into double figures, while Jimenez backed up with a bogey at the eighth and a double-bogey at the ninth. At the par-3 11th, Sandelin pulled three clear of the field after knocking his tee shot to six feet to set up his sixth birdie in 10 holes.
Sandelin made it interesting down the stretch, blowing his approach over the 16th green en route to a bogey that dropped him to minus-10.
But Olazabal was already in the clubhouse at 9-under with a bogey-free 67, and Pettersson recorded back-to-back bogeys at Nos. 15 and 16 to fall three shots back of Sandelin.
The victory was Sandelin's fifth on European Tour and his first since he captured the German Open title in a playoff two seasons ago. That marked his second win of 1999 and earned him a spot on the European Ryder Cup squad for the matches at Brookline.
'It's been two years of a lot of struggling,' Sandelin said. 'From now on I am going to take it one week at a time. Last season (2001) I finished 100th on the Volvo Order of Merit so this season I want to take the two zeroes off.'
He's off to a great start. The BMW Asian Open, which was co-sanctioned by the European Tour and the Davidoff (Asian PGA) Tour, was the first event to count toward the 2002 European Tour Order of Merit.
Jaidee had chances to reach 10-under but came up short with birdie attempts at the last two holes. He finished alongside Olazabal at 279, after a 67 that included five birdies, an eagle and two bogeys.
'Both putts were downhill so I didn't think I would leave them short,' said Jaidee of his missed opportunities. 'It was a little disappointing but it feels great to finish second.'
Sweden's Pettersson shot even-par 72 to tie for fourth place at 7-under 281 with Barry Lane of England, who carded a 3-under 69.
Spain's Jimenez, who like Sandelin was seeking his first win since 1999, turned in a 73 for a share of sixth place with New Zealand's Michael Campbell.
Campbell, whose 6-under 66 was the best round of the day, won the 2000 Johnnie Walker Classic over this same Ta Shee Resort layout.
Vijay Singh, the winner of back-to-back titles in Asia earlier this year at the Malaysian Open and Singapore Masters, shot a final-round 70 to finish with Brian Davis and Stephen Dodd at minus-five.
Full-Field Scores from the BMW Asian Open