He may be one of the best 21-year-old golfers in South Australia, but Nick Thompson is far from convinced he could make it onto a professional tour.

One of 11 trainee pros from clubs around Adelaide who played in a competition at the Mount Gambier Golf Club on Sunday, Thompson showed his talent by shooting a six-under par 66 to win by six shots.

His all-round game was superb, driving the ball a mile, hitting pin-point irons and putting well, his only blemishes being a three-putt bogey on the par-three 6th hole and a bogey on 17.

He also made six birdies, including one on the par-four 18th where his drive finished just off the back off the green.

The icing on the cake, however, was an eagle three on the par-five 15th courtesy of a monster drive and superb nine iron from 145m to about eight feet.

Thompson, who reduced his handicap from 36 to +4 in four years after taking up the game at age 13, is undertaking a four-year traineeship at the prestigious Grange Golf Club.

And while he has shot rounds of seven-under par a handful of times, he said making it on tour takes extraordinary talent.

“I have seen really good golfers not make it,” he said.

“I wanted a way to get into the industry and be able to stay in it so I steered away from turning pro.”

As well as his traineeship, Thompson is also doing a three-year diploma of business which would allow him to become a general manager of a golf club.

“I’ll just see how it’s going after the three years whether I do have a shot at playing on one of the tours,” he said.

“I really want to coach and teach though.”

Thompson was also full of praise for the Attamurra course in what was his first competitive round at the club.

“The greens were the best I have played on all year,” he said.

“And I loved the layout.”

Runner-up was Brodie Whitbread with an even-par 72, while Patrick Kroschel came in third with a two-over par 74.