South African Richard Sterne cruised to a seven-stroke victory over former US Masters champion Charl Schwartzel in the Joburg Open on Sunday.

Sterne, runner-up behind Stephen Gallacher of Scotland in the Dubai Desert Classic last weekend, fired an eight-under final-round 64 for a total of 28-under 260 in overcast conditions at Royal Johannesburg and Kensington Golf Club.

Pre-tournament favourite Schwartzel, who won the Joburg Open in 2010 and 2011 before relinquishing the title to Branden Grace last year, finished with a 66 for a 267 total over the 6942-metre course.

Chilean Felipe Aguilar (67), South African George Coetzee (67) and Portuguese Ricardo Santos (64) shared third place on 268 in the 1.3 million euros ($A1.71 million) event co-sanctioned by the European Tour and Sunshine Tour.

South Africans Thomas Aiken (66), joint overnight leader Trevor Fisher junior (73) and Keith Horne (65) were a shot further back and Italian Lorenzo Gagli (67) and South African Garth Mulroy (67) ended with 270 totals.

The final round at a course in an upscale north-eastern Johannesburg suburb was disappointing with the expected showdown between overnight leaders Sterne and Fisher failing to materialise.

Fisher fell away badly after an eagle on the opening hole and a bogey-free eight-under round brought a sixth European Tour title to Sterne, who has been hampered by back problems.