ENGLAND'S Gary Wolstenholme spreadeagled the field with a course record five-under-par 67 in the opening round of the eighth China Open men's amateur championship at Honichi Golf Leisure Club yesterday. The 1991 British amateur champion fired six birdies against one bogey in a classy display that left his rivals trailing. ''To come all the way here from England, naturally I want to do well,'' said Wolstenholme, who hit 15 greens in regulation on the 7,009-yard layout. Said Wolstenhole: ''I'm very impressed with the course, especially when you consider how young it is. It's a skill course where you have to think about playing the percentages.'' And few amateur golfers anywhere in the world play the percentages better than Wolstenholme, who made birdies at the sixth and ninth to reach the turn in two-under 34. It got even better. A pinpoint wedge to three feet set up another birdie at the 10th. He made it four birdies in five holes by rolling home putts of no more than 14 feet at the 12th and 13th. The birdie barrage continued at the short 16th, but the 33-year-old from Bristol dropped his only shot of the day at the dog-leg right 17th, a tricky par-four measuring 426 yards, where he overshot the green, chipped back but missed his putt for par from eight feet. Going into the second round of the 72-hole event, Wolstenholme holds a five-stroke lead over compatriot David Fisher, the current English amateur strokeplay and matchplay champion. Fisher, winner of last week's Hong Kong Open at Clearwater Bay, returned an even-par 72. It was a mildly disappointing day for China's leading hopes Zhang Lianwei and defending champion Cheng Jun, both of whom finished with 74s to share third place. Zhang's cause was not helped by twice going out of bounds. The leading Hong Kong players are Tang Shu-wah and Hugh Staunton who share fifth position with Tommy Manotoc of the Philippines after rounds of 76.