Bennetts had an excellent amateur career through the 1960s, becoming the first golfer to win the New South Wales Junior Championship three times.

Bennetts turned pro in 1968 and quickly had much success, culminating with his "golden year" of 1971 where he won 12 events.

In the mid-1970s, Bennetts teamed up with fitness trainer Ray Anderson who significantly improved his performance, highlighted by a victory at the 1975 Australian PGA Championship, his biggest win.

[4] A few days later he recorded a solo second-place finish at the New South Wales schoolboys championship held at Ryde-Parramatta Golf Club.

[8] In April, it was announced that he was selected to represent New South Wales for the Australian Junior Interstate Matches for the first time.

[12][14] In May, he played the inaugural New South Wales Junior Mixed Foursomes tournament at Bonnie Doon Golf Club.

[17] In late August, it was announced that Bennetts earned entry into the Australian Men's Interstate Teams Matches representing New South Wales.

Their team "staged a brilliant finish" with birdies at the final three holes to tie Vic Bulgin and Reginald Dunn at the end of regulation.

In the second round, Bennetts shot a "brilliant" 68 (−3) to tie Barry Burgess for the low amateur score.

However, leader Peter Headland "dropped four shots over the last four holes to give Bennetts a chance to beat him."

[35] In September, it was announced he would represent the New South Wales at Australian Men's Interstate Teams Matches later in the year.

[36][30] In October, he played the New South Wales Mixed Foursomes Golf Championship at Ryde-Parramatta with partner Carol Blair.

However, Bennetts and Blair defeated Sharp and Kenny by a shot in a six-hole playoff to win the event.

[44] Later in the year, he successfully defended his New South Wales Mixed Foursomes Golf Championship with Carol Blair.

[45] Bennetts first received significant media attention as a professional for his performance at the New South Wales PGA Championship.

[51] In the third round, despite "blustery conditions," Bennetts scored six birdies to shoot a 69 (−3) and tie Les Wilson for the lead.

[53] In December, he played the New South Wales PGA Foursomes Championship with Vic Richardson, a club pro from Moore Park.

[7] Later in the season, Bennetts recorded top ten finishes at the Brisbane Water Tournament and Aeron Golf Classic.

[58] Two weeks later he won the Roseville purse with a bogey-free 62 (−2), defeating David Graham, Doug Maggs, and Tony Mangan by a shot.

The legendary golfer Peter Thomson referred to Bennetts as one of the top new Australian pros "fresh from the amateur ranks" along with Jack Newton.

[60] According to John Hourigan, golf writer for The Canberra Times, Bennetts was among the top Australian golfers to have turned pro in the 1960s along with Bruce Devlin, Ted Ball, Bob Mesnil, and Graham Marsh.

However, he responded with three consecutive under-par rounds to finish in a tie for 12th with America's Arnold Palmer and Spain's Ángel Gallardo.

Bennetts opened with rounds of 66 and 71 to tie Thailand's Sukree Onsham and Australia's Kel Nagle for the lead.

[82] Bennetts again played well in the final round, this time shooting a seven-under-par 66 to finish in a tie for second with Graham Marsh.

Late in the month he played the Sumrie Better-Ball, a pairs event, with South African Terry Westbrook.

He opened in tie for second place with fellow Australian Stewart Ginn after a 73 (−1), one shot behind leader Tertius Claassens.

[121] During this period of struggle, Bennetts also worked as a waiter, laborer, and strapper at a racehorse stable to help make ends meet.

[126] At the beginning on the 1974–74 season, Bennetts recorded top ten finishes at West End Tournament and New South Wales Open.

"[139] In January 1976, he elected to play in the New Britain Open in Papua New Guinea rather than defend his Australian PGA Championship.

[149] In the middle of 1981, Bennetts sold his Moore Park driving range to fellow professional golfer Geoff Scott.