South African pair Richard Sterne and Trevor Fisher Jr will head into the final round of the Johannesburg Open tomorrow with a five-shot lead over the rest of the field.

Starting the day as joint overnight leaders, there was once again nothing between the pair, who each produced rounds of 68 with closing birdies to move to 19 under par.

Four players are tied for third place including Jaco Van Zyl, who moved into contention with a round of 67, and former US Masters winner Charl Schwartzel, who shot 68.

Fisher, who is yet to win a European tour title, admitted: "A bit of nerves set in there. You try not to think about the lead, but it's there in front of you.

"I was a bit jumpy with the swing and wasn't waiting at the top, so I hit a few bad shots there.

"But I came back nicely with a few birdies. It's just a feeling, and you've got to try and feel comfortable out there as much as possible."

Fisher and Sterne had made their intentions clear by hitting opening birdies on the east course, before Sterne nudged ahead with consecutive birdies on the sixth and seventh.

Fisher wrested the lead with three consecutive birdies of his own, but consecutive bogeys on the 10th and 11th handed the initiative back to Sterne.

Fisher followed his two bogeys with two birdies before both players bogeyed the 15th. Their respective birdies on the final hole ensured they maintained their healthy advantage over the rest of the field.

Chile's Felipe Aguilar and South African George Coetzee both hit rounds of 67 to join Van Zyl and Schwartzel in the tie for third.