Indefatigable flanker Ellis Jenkins was instrumental in helping Wales extend their winning run to nine games as they racked up a 20-11 victory over South Africa on Saturday.
Tomas Francis and Liam Williams crossed for first-half tries for Wales, Gareth Anscombe knocking over two conversions.
Handre Pollard got South Africa on the scoreboard with a penalty before Jesse Kriel crossed for a try early in the second-half.
Elton Jantjies kicked the Springboks to within three points before Dan Biggar banged over two penalties to ensure the home side's longest unbeaten streak since 1999.
"The effort put into it is the habit, we're very pleased with all the wins, there are patches we have to work on but the character is the most pleasing thing," Wales captain Alun Wyn Jones told BBC.
"We can't deny there's a bit of depth developing, credit to the whole squad that have supported each other through the four Tests."
Jones' Bok counterpart Siya Kolisi added: "It was really tough, we played a lot of rugby in our half which was what they wanted. Every time we got into their half we gave away penalties, which made it really tough."
Jenkins, a late call-up to the starting XV after an elbow injury to Dan Lydiate, dominated the loose, produced a couple of vital turnovers and shored up a creaking scrum in a thrilling match at Cardiff's Principality Stadium.
But his outing ended on a sour note as he was stretchered off, on oxygen, after falling awkwardly in the final play of the game.
The victory was Wales' sixth win in 35 games against the Springboks, five of those having come in six games over the last four years. It also gave Wales a first ever four-from-four autumn Tests cleansweep, having gone into the game on the back of victories over Scotland, Australia and Tonga.
Two thrilling Welsh passages showing a slick, clinical side to their play that would have delighted coach Warren Gatland went fully rewarded, Exeter prop Francis first crashing over from short range after Jenkins fooled South African hooker Malcolm Marx with a smart dummy.
Liam Williams crossed for the home side's second try on the quarter hour, taking a lofted mis-pass from Anscombe and cutting back inside the covering Siya Kolisi.
Tries: Francis, Williams
Cons: Anscombe 2
Pens: Biggar 2
South Africa 11
Pens: Pollard, Jantjies
FRANCE vs FIJI
Fiji beat France 21-14 to claim their first victory over the French in more than 60 years on Saturday.
The teams have faced each other on 10 occasions since their first fixture in 1964 and the Pacific Islanders made history in Paris despite having two tries disallowed by the television match official.
Tries: Guirado 2
Cons: Serin 2
Tries: Radradra, Tuisova
Pens: Volavola 3
SCOTLAND vs ARGENTINA
Sean Maitland has scored a try 15 minutes from time to earn Scotland a hard-fought 14-9 victory over a profligate Argentina at Murrayfield and end the year on a winning note.
The winger was sent over on the blind side by Stuart Hogg after a smart piece of thinking that caught out the South American visitors and brought to life a dour tussle on Saturday.
Greg Laidlaw kicked three penalties for Scotland but Nicolas Sanchez missed four out of seven kicks for the Pumas.
Scotland were 6-3 ahead at half-time as Argentina suffered a fifth successive test defeat which has included losses in Ireland and France during their November tour programme.
For Scotland it was a second victory in four internationals this month, having beaten Fiji but losing away to Wales and at home last weekend to South Africa.
Argentina looked more adventurous in the first half but were met by a sturdy Scots defence as both sides failed to generate any real excitement.
Laidlaw, the man of the match, was accurate with his two first-half efforts but Sanchez got over only one in three attempts.
But straight after the break he brought parity with a successful effort only to miss another kickable opportunity soon after. Laidlaw made it three from three in the 56th minute, restoring the Scotland lead 10 minutes before Maitland's try injected some life into a subdued sellout crowd.
Argentina won a penalty in front of the posts with some six minutes to go but surprisingly opted to kick to reduce the deficit when a scrum or lineout might have offered to opportunity for a much-needed try.
Sanchez reduced the score to 14-9 but time quickly caught up with the Argentines as they sought to advance forward again for a last-gasp score and Scotland were able to see them off.
Pens: Laidlaw 3
Pens: Sanchez 3
IRELAND vs USA
Ireland's second-string overpowered an ultimately outclassed United States 57-14 in Dublin on Saturday to end a brilliant year on a high.
Victory meant Joe Schmidt's reigning Six Nations Grand Slam champions had lost just the once in 12 Tests in 2018, an 18-9 defeat by Australia in Brisbane in June in the first of a three-match series.
Ireland coach Schmidt made 14 changes to the starting side that enjoyed a
16-9 win over his native New Zealand, the reigning world champions a week earlier, with centre Garry Ringrose the only player to keep his place.
"There were a couple of new combinations out there," said Ringrose. "We had to stick to our guns and reacting to conceding a try or two was a really good learning curve.
"There are still the same set of standards for everyone in the group, whether it was four weeks ago when we started this, right to the end.
"It was about upholding those standards right to the finish and making it a successful autumn," he added.
Saturday saw Munster wing Andrew Conway run in a hat-trick of tries, with Ireland scoring eight in all, although the Eagles were still in touch at just
24-14 down at the break through a try from Joe Taufete'e and a penalty try.
But Ireland, now one of the favourites for next year's World Cup in Japan, scored 33 unanswered points in a second half which saw Conway complete his treble and Tadhg Beirne, Stuart McCloskey, Quinn Roux and John Ryan also score tries.
Tries: Conway 3, Beirne, McCloskey, Roux, Ryan
Cons: Carbery 7
Tries: Taufetee, Penalty
ITALY vs NEW ZEALAND
New Zealand have smashed Italy 66-3 in Rome, finishing their European tour with an 10-try romp and leaving coach Steve Hansen with plenty to consider as he looks to settle on a squad to defend their World Cup title next year.
Hansen retained just four players from the starting team that lost to Ireland last week, and a few of his new picks took full advantage of the opportunity on a grey Saturday and on a damp pitch in front of a big crowd at Stadio Olimpico.
Winger and man-of-the-match Jordie Barrett scored four tries and fullback Damian McKenzie, whose selection at fullback has been questioned by some rugby pundits at home, scored three.
Five-eighth Beauden Barrett, seldom under the kind of pressure he felt last week against Ireland in Dublin, also scored a try before being replaced in the second half by Richie Mo'unga who has been building a claim to the starting five-eighth spot.
"It's been a great tour for us," Hansen said after the game.
"We have found some younger players who have challenged some of the senior players and have said: 'Hey, we are here'. No doubt we will go back and solidify our thinking and our selections."
Looking back over the past three weeks, Hansen said the All Blacks had shown calm and mental strength to come back from a 15-point deficit to beat England at Twickenham and that the defeat in Dublin had only served to make the team hungrier.
"I know that (loss) will make us a little hungrier and it's always good if you go to the table hungry... You won't win the World Cup unless you're hungry."
Skipper Kieran Read, who led the haka for the first time before the game, said the team had learned a lot from the tour and were feeling good with just a handful of Tests before the World Cup, which gets underway in September.
"We are in a pretty good spot right now," he said.
The Azzurri managed a single penalty in a physical encounter up front. Even the referee, Andrew Brace, had to be substituted in the first half after he collided with a player.
"They are a very, very good team," said Italy's coach, Irishman Conor O'Shea.
"They are at a different level."
New Zealand 66
Tries: J Barrett 4, McKenzie 3, Perenara, Laumape, B Barrett