Seven birdies and an eagle saw home favourite Charl Schwartzel storm through the field on Friday to share the lead with Italian Marco Crespi after the end of the second round of the South African Open.

Schwartzel, who is South Africa's top ranked golfer but never won the tournament, also bogeyed three holes at the Glendower Golf Course on the outskirts of Johannesburg as he posted a seven under 65 to share a 12-under total of 132 with the 35-year-old Italian.

Crespi came through the qualifying School last week for the first time in 11 attempts and is playing his maiden tournament since winning his European Tour card. He hit six birdies in his round of 67.

"My putting and chipping was pretty amazing," he told reporters after going into the clubhouse as the early leader.

"I was expecting a good tournament because I was playing well. Obviously not this big but I'm confident about the weekend. I'll just try to remain calm and play my game," said Crespi.

Dane Morten Orum Madsen, a rookie last year, lies third on 11 under, one ahead of Christian Basson of South Africa.

Overnight leader Matthew Nixon from Britain hit a par 72 in the second round to drop to four behind the leader.

Simon Thornton is best of the Irish on two under after a 72, while Gareth Maybin is level after two rounds.

Peter Lawrie is one-over-par, Damien McGrane and Michael Hoey are both three over, and Paul McGinley is back at the tail of the field on seven-over.