Early in the year at the Malaysian Open, he finished one behind Japan's Takashi Murakami, tying Walter Godfrey and American Marty Bohen for second.
[6] On 23 October 1972, Onsham finished runner-up to American Bob Murphy at the 1972 Wills Masters, an event on the Australian Tour held outside of Sydney.
[7] Two weeks later he posted another runner-up in Australia at the Dunlop International, four shots behind Tony Jacklin, finishing tied for second with David Graham.
[1] Two years later, Onsham won an event, the Malaysian Dunlop Masters, defeating Australia's Ted Ball and Malaysia's Bobby Lim by two shots.
A young Payne Stewart made a 20-foot birdie putt to defeat him and Taiwanese golfers Hsu Chi-San and Chen Tze-chung on the first playoff hole.