Luke Donald started his second round in stunning fashion to move level with Ross Fisher at the top of the Nedbank Golf Challenge leaderboard.
The former World Number One birdied seven of his opening ten holes, completing the front nine in just 30 strokes, to move alongside his fellow Englishman on eight under.
Although Fisher lost his advantage, he still had a blemish free opening nine holes.
The 34 year old struggled to replicate the highs of his opening round performance, though, collecting shots on just two holes compared to four at this stage yesterday.
Marcel Siem started his second round in contrasting fashion, following up a bogey on the first with an brilliant eagle on the 569 yard par five second, before making two consecutive birdies from the sixth.
However, a bogey on the eighth left the German two shots off the lead on six under.
Siem was two clear of the chasing pack, with Frenchman Alexander Levy, South African Tim Clark and Scot Stephen Gallacher all on four under.
Earlier, Welshman Jamie Donaldson was forced to withdraw from the tournament due to a severe migraine.
