Max Homa made a stunning eagle at the ninth to take a two-shot lead into the back nine at the Nedbank Golf Challenge.
The American, who held a one-shot advantage overnight, had been caught by a stunning Thorbjørn Olesen charge as the Dane made six birdies in an outward 31.
However, no sooner had he been joined at the top of the leaderboard than World Number Eight Homa fired a sensational approach over the water to 18 feet.
The eagle added to birdies at the second, third, fifth and sixth – as well as a bogey at the fourth – saw Homa match Olesen's front-nine 31 to lead by two on 18 under.
Olesen had opened up a three-shot advantage over the rest of the chasing pack, which was headed by his compatriot Nicolai Højgaard and England's Dan Bradbury on 13 under, with American Justin Thomas fifth on 11 under.
