Fleetwood claimed his maiden European Tour title, the Johnnie Walker Championship at Ryder Cup venue Gleneagles last year, four days before the qualifying race for September's contest got under way.
The 22-year-old was quick to admit France's Victor Dubuisson and Holland's Joost Luiten, his nearest challengers at Durban Country Club, are better placed to make Paul McGinley's Europe side, but insists an "exceptional" year can still secure a debut in the clash with the USA.
"They are a lot closer than me," said Fleetwood after a third-round 69 saw him reach 10 under par, one ahead of Dubuisson and Luiten, who shot 69 and 70 respectively. "I would like to win tournaments and the Ryder Cup is something that will happen if I have an exceptional year. I probably have to win three times to get in the team and it would be awesome to win here."
Fleetwood was the youngest winner of the second-tier Challenge Tour in 2011, but only kept his card at the end of his rookie European Tour season thanks to a first top-10 finish of the year in the final event, coincidentally in South Africa.
Victory at Gleneagles helped him finish 26th in the Race to Dubai last year, the win coming with a birdie on the first hole of a play-off on the Centenary Course with Argentina's Ricardo Gonzalez and Scotland's Stephen Gallacher.
"I learned from that that I can win, which is huge at this level," Fleetwood said. "Thinking you can win and knowing you can are miles apart."
Dubuisson, winner of the Turkish Airlines Open in November, is third on the European Ryder Cup points list and would be within sight of securing his place should he claim the £420,000 first prize today.
The 23-year-old said of his third round: "I've never hit the ball so badly, but my short game saved me. I could have been three or four over.
"I was a little tired this morning - I didn't sleep well - and I missed a lot of shots. The win [in Turkey] gave me a lot of confidence, but you can still have bad rounds."
Defending champion and local favourite Louis Oosthuizen led with three holes to play, but ran up a triple-bogey seven on the 16th after hitting his second shot into thick undergrowth and having to declare it unplayable. That meant a 71 and fourth place, two behind Fleetwood.
Fellow South African Branden Grace is a shot behind Oosthuizen on seven under, with Welshman Jamie Donaldson another stroke back alongside France's Raphael Jacquelin.
England's Paul Casey shot the lowest round of the week to lie four under, giving the 36-year-old another reason to be cheerful after learning last week that his American coach Peter Kostis had been given the all-clear after his battle with cancer.
After receiving some advice from Kostis following a second round of 75, Casey improved by 10 shots yesterday to boost his chances of climbing into the world's top 64 in time for the WGC Accenture Match Play Championship in February.
"I'm really pleased with that because I struggled on Friday and sent a panic text to Peter," Casey said.
Of the two Scots taking part in Durban, Colin Montgomerie was in a tie for 15th place - seven off the lead - after a 69, while Stephen Gallacher's 72 left him in a share of 32nd.