The 35-year-old Spaniard set up his triumph with the shot of the week at Hong Kong Golf Club. After driving into the right rough at the 410-yard, par-4 18th hole, Olazbal knocked his 5-iron approach onto the front of the green and his ball rolled to within inches of the cup for a closing birdie.
'I didn't expect that last shot and you always need a bit of good luck,' said Olazbal, who posted his second straight 64 to finish atop the leaderboard at 22-under-par 262. 'I don't think I've won with three closing birdies and it was excellent. This is very special and it was fantastic to win as it was a tight finish.'
Norway's Bjornstad, 22, who fired a course-record 61 Saturday to take over the top spot, had a chance to force extra holes but missed a 20-foot birdie try at the last. He carded a 4-under 67 for 21-under and second place, the best finish of his career.
Playing in the final group with Olazbal and Bjornstad was 21-year-old Australian Adam Scott, who led after the first round and for much of the day Sunday. Scott was part of a three-way tie for the lead heading into the 72nd hole but his bunkered tee shot resulted in a bogey that left him alone in third at minus 20.
Bjornstad and Scott were tied at 21-under, two shots ahead of Olazbal, heading into the last three holes. But Olazbal, who may have won the tournament in a runaway had he putted better the first three days, drew alongside the leaders by draining birdies from 15 and 18 feet at the 16th and 17th, respectively.
Meanwhile, Bjornstad left his two long birdie attempts short and Scott just missed a pair of 30-footers.
Bjornstad seemed to have the advantage at 18 when he placed his drive in the middle of the fairway. Olazbal's tee shot cleared the right fairway bunker but stopped in the rough and Scott found the sand with his drive.
Scott then attempted to cut his ball around the water fronting the final green but his shot stayed left and finished in the rough just off the putting surface.
Olazbal went next and pulled off the shot perfectly.
'I had to punch it and didn't have much green to work with, but I had a good slice of luck,' he said. 'I executed the shot the way that I wanted. But I always say you need a bit of luck ... if it had pitched three feet more, that ball would have landed well past the pin.'
Bjornstad, whose approach to 18 left him two putts away from a closing par, later gave credit to the heroics Olazbal produced over the final few holes.
'Ollie finished great to win the tournament,' said the young Norwegian. 'He just came from behind and took it away from us.'
Scott, still searching for his second win after several near-misses since breaking through at the Alfred Dunhill Championship in January, agreed.
'When Ollie finishes three, three, three, there is nothing much you can do,' said Scott, who shot a final-round 67. 'He hit a great shot at the last.'
Olazbal was two shots off the pace at the start of the round and never led until his winning birdie. He matched birdies with Scott at the second and third holes to stay one behind the Aussie, but a bogey at the fifth dropped Olazbal two strokes back at 16-under.
Although birdies at the eighth, ninth and 12th lifted Olazbal to 19-under, Scott added three birdies of his own and Bjornstad came to life with five birdies over a six-hole stretch to share the lead at 21-under-par.
But while it turned out the young guns were done making birdies, the sage Spaniard was just warming up.
Olazbal earned the first prize of $113,000 to remain second behind Jarmo Sandelin of Sweden on the new season money list. He finished runner-up to Sandelin at last week's BMW Asian Open in Taiwan, the first event to count toward the 2002 European Tour Order of Merit.
England's Mark Foster, No. 1 in the 2001 Challenge Tour rankings, finished solo fourth at 19-under, one stroke ahead of Sweden's Carl Pettersson, who recorded his second top-five finish in as many weeks.
Swede Anders Forsbrand, Andrew Marshall of England and Welshman Mark Pilkington tied for sixth place at 17-under. Sandelin rounded out the top 10 at 16-under with second-round leader Yeh Wei-Tze of Taiwan and Englishmen Brian Davis and Simon Dyson. Dyson was the defending champion.
Thailand's Thongchai Jaidee, who finished second with Olazbal last week, claimed the Davidoff Tour Order of Merit crown after tying for 13th Sunday with England's Gary Evans and New Zealand's Michael Campbell.
The Hong Kong Open, which was co-sanctioned by the European Tour and Davidoff (Asian PGA) Tour for the first time, was the season-ending tournament on the 2001 Davidoff Tour.
Full-field scores from the Omega Hong Kong Open