- Scottish golfer Scott Jamieson leads Volvo Golf Champions tournament by five shots
- His second European Tour win would give him a debut at World Golf Championships event
- Former British Open champion Louis Oosthuizen tied for second at Fancourt
- Fellow major winners Padraig Harrington, Paul Lawrie and Ernie Els also in contention
Scott Jamieson knows all about struggling in golf's lower echelons, but the Scotsman has been living the dream in the past month.
He won his first European Tour event at the rain-shortened Nelson Mandela Championship in December, earning a place at another South African tournament -- this week's Volvo Golf Champions.
The 29-year-old will take a five-shot lead into Sunday's final round at Durban Country Club, knowing that even greater opportunities await if he can hold off the likes of major champions Louis Oosthuizen, Padraig Harrington, Paul Lawrie and Ernie Els.
Another victory will earn him a place at next month's Accenture Match Play in Arizona, which would be his debut appearance in a World Golf Championships event.
Having started this week at a career-high 100th in the world rankings, it would also push him closer to the top 50 and his first outing at the Masters in Augusta in April.
It's a far cry from his early days as a professional, slogging around minor circuits before finally making the step up to the European Tour in 2011, making the top 60 on the money list in his first two seasons.
"I was just in the abyss, so I guess slumming around in the lower leagues helps build your character," said Jamieson, who was an amateur at Augusta State University before turning pro in 2006.
"I was fortunate to keep playing when money was not necessarily being chucked at me."
On Saturday he carded a four-under-par 68 to move clear of 2010 British Open champion Louis Ooosthuizen (74), Thailand's Thongchai Jaidee (73) and France's world No. 187 Julian Quesne (67).
"It was another great day. I didn't play as well as I did the first two days, especially tee-to-green, but managed to score well and that's the main thing," Jamieson said.
That chasing trio ended the day tied for second on 10-under 206, two shots clear of three-time major winner Harrington (67) and Ryder Cup winner Francesco Molinari (68).
Jamieson's compatriot Lawrie, the 1999 British Open winner, was tied for seventh on 209 with Ireland's Shane Lowry and Englishman Danny Willett after all carded 70.
Els, the current holder of the coveted Claret Jug, was tied for 11th on 211 in a group also including defending champion and fellow South African Branden Grace.
Meanwhile, rookie Russel Henley took a two-shot lead at the halfway stage of the PGA Tour's Sony Open in Hawaii.
The 23-year-old shot his second successive seven-under 63 on Friday to move ahead of fellow Americans Scott Langley (66) and Scott Piercy (64) at the $5.6 million tournament in Honolulu.
Henley's playing partner Langley, also making his debut on the U.S. circuit, had led after a first-round 62.
Dustin Johnson, who won the wind-hit season-opening Tournament of Champions at Kapalua on Tuesday, pulled out after nine holes of his second round due to illness.