Springbok captain Victor Matfield paid tribute to his side's staunch defence as the world champions withstood a late rally from Wales to win 25-29 at the Millennium Stadium.
The victory kept South Africa's hopes of a Grand Slam alive after they brushed aside Ireland last weekend.
South Africa were 17-9 behind at the break but scored 17 unanswered points in the space of seven minutes to grab the initiative from Wales.
Wales refused to cave in and mounted a fierce late rally but couldn't breach the green wall.
"I'm very proud of the boys, they showed great character," said Matfield. "Wales put us under pressure and it was a great game for the spectators to watch.
"Well done to Wales, they really came out and played well. "(Defending) is something we really worked hard on (in training) and it came through and we were happy with that," he added.
Referring to a possible Grand Slam, Matfield said: "I don't know. There's still a fair way to go. We're focusing on Scotland and that's going to be another huge game. We will enjoy tonight and then start fresh from zero on Monday again."
Porthcawl recently received a WRU facilities grant and funding from Natwest RugbyForce in order to give their changing rooms a facelift. This came after receiving £10,000 in a WRU facilities grant last year to tarmac their car park. The improvements have already helped to make the club more accessible, not only for their own members and players but for the whole community.
The Welsh Rugby Union has launched a new, accredited Safeguarding and Protecting Children course - funded by the WRU and delivered in partnership with Sport Wales and the NSPCC - fo rugby club volunteers around Wales.
The SWALEC semi-final draws threw up some mouth-watering clashes in the Cup, Plate and Bowl as the 12 teams aim for the Millennium Stadium Finals Day. All the semi-finals are to be played on the weekend of April 12.
Welsh whistler Rhys Thomas continues to scale the heights of the game as he prepares to be an official in this weekend's Hong Kong Sevens tournament, undoubtedly the showpiece event on the World Series calendar.
Wales International Ian Evans and Wales and Lions legend Scott Quinnell swapped rugby balls for paint pots at Tonna during the RBS 6 Nations. They surprised club players with a special clubhouse makeover to launch NatWest RugbyForce 2014 - a programme developed in partnership with the WRU to make rugby clubs stronger businesses by improving and renovating their facilities with the support of volunteers and the local community.
Fresh from claiming the Bowl honours in Tokyo last Sunday, the Wales Sevens squad have settled into their routine as they prepare for this weekend's Hong Kong tournament where Iolo Evans is aiming high, as WRU TV's Graeme Gillespie discovers.
The Welsh Rugby Union has recently teamed up with Prostate Cymru to help the charity launch its latest campaign to raise awareness of the disease. Members of the Wales squad helped produce a short video and promotional material for the campaign titled 'The Best Defence - is to know the FACTS'.
Defending champions Coleg Sir Gar reached their second consecutive Millennium Stadium final as they defeated Coleg Gwent in the WRU Wednesday Under 18 play-off. Watch highlights of their narrow 10-8 win here.