Warren Gatland's men sealed their 100% record with a 20-11 victory against the Springboks
Wales completed their first ever Under Armour series clean sweep as they overcame South Africa 20-11 to win their ninth test match in a row.
Warren Gatland's side are on their best winning run since 1999 and is their fourth victory in a row against the Springboks.
The hosts crossed for two first half tries courtesy of tight-head prop Tomas Francis and full back Liam Williams with Gareth Anscombe and Dan Biggar kicking 10 points between them.
Jessie Kriel claimed South Africa's only try while Handre Pollard and Elton Jantjies contributed six points to their cause.
South Africa went on the attack in the early stages of this test match with late call-up Cheslin Kolbe sparking them into life.
The winger beat three men before shifting the ball wide with Pieter-Steph Du Toit's foot brushing the touch-line on his way to the try-line.
But such an early scare only served to wake the hosts up with Williams launching a searing counter attack into the Springboks half.
With Wales on the attack in South Africa's 22 Malcolm Marx bought a dummy from Ellis Jenkins who sliced through the visiting defence before putting Francis over for his first try in 36 test matches.
Gatland's side were playing with the confidence of a side who had won their previous eight test matches as they stretched their visitors with some lovely interplay between backs and forwards.
And Wales' ambitions paid off with a second try in the space of six minutes. The home side were camped in South Africa's 22 with Williams crossing at the far right-hand corner after a gorgeous pass from Anscombe.
Pollard opened the scoring for the Springboks with a successful penalty attempt from 40 metres out after Adam Beard was penalised for playing the ball on the floor.
Wales were forced to defend for the remainder of the half as Embrose Papier broke clear from the blindside of a lineout.
The lively scrum half went 20 metres before putting boot to ball but lost it forward as he attempted to regather.
South Africa lay siege to the Welsh try line for the remainder of the first half and Jesse Kriel came within a whisker of grabbing their first try when he powered his way over from short range.
Referee Luke Pearce referred the decision to the TMO with the television replays showing Jenkins' hand underneath the ball.
But the Springboks attempted to batter their hosts into submission but repelled time and time again by a resolute Wales defence.
And with the clock having turned red Jenkins was yet again to the fore with a crucial turn over which allowed his side to turn around with a 14-3 lead.
The visitors started the second half like a house on fire with the home side force to repel wave after wave of South African pressure.
But the pressure finally told with Kriel squeezing in at the corner after a sensational pass from Wasps full back Willie Le Roux.
Jantjies narrowed the gap to a mere three points with a successful penalty after Wales were pinged for holding on at the breakdown.
Wales forced a momentum shift when Jantjies failed to take a high ball. Elliot Dee ripped the ball free and fed Biggar who chipped into the corner for Justin Tipuric to win a penalty as Aphiwe Dyanti was penalised.
Tipuric's intervention allowed Biggar to extend Wales' lead to six points with a penalty from the far right-hand side.
Jonathan Davies put Wales into the ascendancy as he sliced clean through the Springboks defence before offloading to Rob Evans who was then brought down in South Africa's 22.
But Davies' break forced the Boks to infringe allowing Biggar to put Wales two scores ahead. The Springboks kept pushing forward but they had no answer to Wales' heroic defensive effort.