South Africa responded to an early setback with 23 successive points, overpowering France 37-15 in the second Test to win the three-match series with a game to spare.
The Springboks shrugged off a third-minute try by France fullback Scott Spedding to eventually score four of their own in their best performance under coach Allister Coetzee.
On top of the series victory, it was the Boks' biggest step on the road back from a woeful 2016 season, which included a record defeat by the All Blacks the last time they played in Durban.
"Unbelievable performance," Coetzee said.
"Very proud of how this team has grown over the last nine months. Nine months ago we were all sitting here in a lot of pain."
Flanker Siya Kolisi set up South Africa's first and last tries, and scored one himself to be the home team's standout player at Kings Park.
He provided the final pass for centre Jan Serfontein to go in for the first try, then intercepted for his score.
Replacement prop Coenie Oosthuizen barged over late on and another surging Kolisi break set up flyhalf Elton Jantjies for the final try, capping the Boks' dominance over a France team that was back to near full strength following the first Test and expected to provide a sterner challenge at Kings Park.
The challenge didn't materialise.
"Now we have to focus on the last game, and I said to my players we have to play our best next weekend," France captain Guilhem Guirado said.
South Africa kept France scoreless for an hour after Spedding's try, backing up some incisive attacking play with long periods of gutsy defensive work for a second straight.
Trailing 23-7, flyhalf Francois Trinh Duc kicked a penalty midway through the second half, with France settling for three points after it couldn't find a way through the Springboks during a 15-minute spell of pressure.
Oosthuizen went barging through three France players soon after to reassert South Africa's superiority.
Kolisi made sure South Africa had the last say. He broke downfield to set up a late try for Jantjies, who collected 22 points on the night with a try and five out of six shots at goal.
Reuters
