PRETORIA, March 3, 2013 (AFP) - Van der Walt fired a five-under-par final round 67 for a total of 267 over the Ernie Els-designed Copperleaf Golf and Country Estate while Fichardt closed with a 69 on the 7,791-yard (7,124-metre) layout.
A two-metre, 110-kilogram giant, western Cape-born Van der Walt was one shot ahead of four-time European Tour winner Fichardt at the turn and extended it with a birdie at the par-five 15th on a hot, overcast afternoon.
Both title challengers parred the last three holes and Van der Walt collected a 237,750-euro ($310,690) cheque and a three-year exemption from qualifying for European Tour events.
The 30-year-old winner of the inaugural Tshwane Open was a model of consistency over the four days of a tournament hit by delays on Friday and Saturday when thunderstorms rolled over the course south west of here.
He had only one bogey over his 72 holes -- at the par-four 10th during the closing round -- and a solid tee-to-green game set up an unexpected success in a 156-field that included three former Major title-holders.
"I hit the ball really well this week and probably missed only six or seven greens in regulation," said the slightly nervous champion after receiving his cheque and trophy.
"My tee-to-green game was good, my putting solid, and to bogey only one hole throughout the tournament on such a long and challenging course was really awesome.
"Among the turning points was dropping a birdie putt at 12 -- I was desperate for another birdie to get to five-under and once the ball went into the hole I felt I was in control.
"My goal was to shoot 10-under for the wekend and my focus was reaching five under for the round today. I am really happy that I played well and won because you can play well and not win."
Van der Walt said the victory lifted a major concern off his shoulders as he was beginning to wonder if he had the ability to win a tournament at the highest level.
"You start doubting yourself and, at 30, you start to wonder if you are good enough. This victory proves that I am. Golf is a game where you do not get a lot of chances to win and to do it is fantastic."
The often hot putter of Fichardt cooled during the final round and he never looked like overtaking Van der Walt during the closing holes while co-overnight leader Charl Coetzee of South Africa closed with a par 72.
Chilean Mark Tullo, the other member of the quartet topping the leaderboard after the third round, crumbled to a 77 after needing 42 strokes to cover the back nine.
Former British Open champion Darren Clarke of Northern Ireland closed with a 69 and there was a 75 from 2012 Ryder Cup-winning captain and twice US Masters title-holder Jose Maria Olazabal of Spain.
Leading Tshwane Open scores after the final round at the par-72, 7,791-yard (7,124-metre) Copperleaf Golf and Country Estate Sunday (RSA unless noted):
267 - Dawie van der Walt 68-65-67-67
269 - Darren Fichardt 65-71-64-69
270 - Louis de Jager 71-65-65-69
271 - Peter Uihlein (USA) 68-66-68-69
272 - Bjorn Akesson (SWE) 66-75-66-65, Charl Coetzee 67-65-68-72, Danny Willett (ENG) 68-68-70-66
273 - Morten Orum Madsen (DEN) 70-67-69-67, Graham van der Merwe 70-66-68-69
274 - Desvonde Botes 69-70-71-64, Vaughn Groenewald 68-70-70-66, David Howell (ENG) 67-69-67-71, Hennie Otto 71-68-68-67, Jake Roos 69-67-69-69, Romain Wattel (FRA) 70-66-71-67
275 - Ross McGowan (ENG) 73-68-68-66, James Kamte 69-70-71-65, James Kingston 70-72-68-65, Garth Mulroy 69-70-69-67, Justin Walters 71-71-66-67