Fisher, after a brilliant 62 on the West Course, and Sterne, who shot a superb 65 on the tougher East Course, are both on 15-under-par, but the names of Coetzee (-12) and Schwartzel (-10) loom dangerously just below them on the leaderboard.
Sterne held a share of the overnight lead with Germany’s Maximilian Kieffer on eight-under-par and the winner of the 2008 Joburg Open immediately went to nine-under with a birdie on the par-five first hole.
Sterne’s strategy of minimising mistakes obviously paid off as he completed a second bogey-free round and collected three more birdies on the front nine and three coming in, including successive birdies on the last two holes.
“I was quite conservative, you have to be on this course, and my game didn’t feel great but I putted well and had a couple of good up-and-downs,” Sterne said.
Fisher has been a Sunshine Tour competitor since 2002 but has become one of the leading players only recently, finishing fourth and ninth on the order of merit in the last two years and being named as the 2012 Players’ Player of the Year earlier this week.
He looked ready to become a regular European Tour contender on Friday as he roared through the back nine in five-under, including three successive birdies to end his round, having earlier eagled the par-five second hole.
“I’m a late bloomer and I think I’ve matured in the last couple of years, but I need to get to the next level now,” the 33-year-old said.
“I was in a happy place out there, everything just happened for me and I sank the putts I needed to sink. I was patient, walked slow and did everything slow. You’ve got to be in the moment, you can’t think about your score … I think that’s the secret to scoring low around here: not trying to make birdies, but trying to hit good shots,” Fisher said.
Coetzee, who shot a phenomenal 64 on the East Course, was playing in the same three-ball as Sterne and he said he had fed off the success of his fellow Pretorian.
“Richie was getting a birdie every other hole so that made me want birdies too. I made some nice putts early on which gave me momentum and I hit the ball great in the stretch. I was pretty happy with my game, except for my long putts, I left a lot short,” Coetzee said.
Schwartzel, who missed the cut when defending his title last year, is cosily positioned just five shots off the lead heading into the weekend, after shooting a 65 on the West Course.
“There’s still a long way to go and Trevor Fisher is playing fantastic golf, but at least I’m still in range. My ball-striking has been good, where I left off last year. So the big thing is that I’m hitting the ball well and giving myself chances. I just need to make more putts from short range,” Schwartzel said.
Fisher, however, said he was ready to make the step up and win his first European Tour co-sanctioned event, having triumphed seven times on the regular Sunshine Tour.
“I’ve been here for 10 years and it’s been a good stepping stone to the European Tour. But I’ve stepped on a lot of stones now and it’s time to get to the top,” Fisher said.
South African Keith Horne and Chile’s Felipe Aguilar are tied with Schwartzel on 10-under, having both shot 66s on the East Course.
Kieffer could only manage a par-72 on the East Course and slipped down into a tie for 11th.