Glenelg's Jack Buchanan survived a playoff and Queenslander Sakura Sugiyama ground out the win in the stroke play championships at the South Australian Amateur at Mt Osmond today.

Buchanan's victory at the third playoff hole against Royal Adelaide's Billy Cawthorne was remarkable not only because of the length of the playoff, but in where he came from.

Cawthorne had the championship in his grasp with a big lead as he stood on the 18th tee, but he drove out of bounds, almost repeated it with his third shot, and ultimately took a quadruple-bogey nine that sent the men's championship to a playoff.

Ultimately they were tied at even-par 140 and it was not until the 19-year-old Buchanan putted out for his birdie four at the last that he knew he was required to play some more golf. "I wasn't expecting it," he said. "I was just playing my game, and I can't complain."

Previously a state team member and Vardon winner as the top SA player, he has also won a Pacific Games gold medal but this was Buchanan's biggest win at open-age level.

Queenslander Sugiyama, 17, carded a 75 today in windy conditions to win the women's by a shot from Celine Chen from Joondalup in Western Australia.

It was her first win at senior level although she has previously represented Queensland at schools level. The daughter of two Japanese immigrants, she also swam and ran cross country for her state before focusing on golf from the age of 13.

Today, she said she played "steady golf" to win.

"My Dad caddied for me and we had to do the live scoring, so I knew that I was near the top, but I didn't look so I didn't know for sure until the end," she said. "I was just focusing on my own game."

The matchplay section of the championships begins tomorrow morning at Mt Osmond.

Women's stroke play scoring

Men's stroke play scoring