(CNN) -- Belgian Nicolas Colsaerts fired a remarkable nine birdies in his last 11 holes to card a course record 64 in the opening round of the Volvo Champions tournament at Fancourt, South Africa.
The 29-year-old, who won his first European Tour event in last year's China Open, holds a four-stroke lead after his impressive nine-under-par round in benign conditions.
England's Tom Lewis and South African pair Thomas Aiken and Branden Grace -- the winner of last week's Joburg Open -- lead the chasing pack, with former British Open champions Padraig Harrington and Louis Oosthuizen among a group of four players a further stroke behind in the 35-player event only open to European Tour winners.
"This is probably the best round I've ever had -- it's quite a serious test of golf," Colsaerts, who vies with Alviro Quiros of Spain as the longest hitters in Europe," told the European Tour website.
"I can reach most of the par-fives in two so it's quite a bonus when you get to birdie the par-threes," he added.
Grace, who only qualified for the tournament after winning last week, told reporters: "I missed a couple of short ones but I kept hitting the ball well and giving myself chances. It will be nice to see how I can follow it up."
Home favorite Ernie Els dropped two shots on the first three holes but birdies on the final three holes saw him finish on two-under 71.
Colsaerts' opening lead is the eighth-largest advantage after 18 holes in the history of the European Tour.