Stevens carded a near-flawless 10-under-par 62 to open up a four-shot lead over Luke Brown.

Stevens began his front nine with a run of five consecutive birdies on the third, fourth, fifth, sixth and seventh holes before dropping a shot on the eighth to make the turn in 32.

He produced a flawless back nine, adding six more birdies on the 11th, 12th, 14th, 16th, 17th and 18th holes to card an inward nine of 30.

Brown, who sits in second place, signed for a flawless six-under-par 66. He carded birdies on the second, fifth and sixth holes for an outward nine of 33 before adding further birdies on the 10th, 11th and 18th holes to return in 33.

Steven Le Roux, Dillon Germishuys, Keagan Thomas, Deon Germishuys and Ockie Strydom are tied for third place on five-under-par 67.