Paisley, 31, finished with a tournament total of 21 under-par, three shots ahead of home favourite Branden Grace (68), the World No.30 and highest ranked player in the field.

It was another round of consistent golf from Paisley, whose wife Keri acted as his caddie this week with his regular bagman on holiday.

He only dropped three shots over the four days and improves on his previous best European Tour finish of third at the 2015 BMW International Open.

"I just can't believe it to be honest," Paisley said at the trophy presentation. "I just played great, I played out of my skin. I didn't think I was capable of playing that well to be honest."

Paisley had special praise for his wife, the first time she has carried his bags.

"I can't say enough about how good a job she did all week. It is her first time as a caddie and she didn't put a foot wrong. I can't thank her enough."

Chris Paisley celebrates victory on the 18th green watched by Branden Grace at the BMW South African Open Championship. PHOTO: Warren Little/Getty Images.

Starting one shot behind Paisley overnight, Grace had briefly hit the front after he started his round birdie-eagle.

Yet a double-bogey on the sixth for Grace restored the lead for the Englishman, who held on to his advantage with birdies at regular intervals.

South African JC Ritchie (65) finished third after a colourful final round that included two eagles, six birdies and three bogeys to leave him at 16 under-par.

His previous best finish on the European Tour was tied for 23rd at the Tshwane Open in 2016.

Tournament host Ernie Els (69) finished at eight under-par, tied for 31st position.

The tournament is the second oldest Open championship in the world having first been formally played in 1903.