Warren Gatland says his Wales players are fully aware they can achieve "something special" against South Africa on Saturday.
Wales have won four of the last five encounters with the Springboks, and they are also chasing a ninth successive triumph against all opponents, which would equal their longest unbeaten run since 1999.
And they go into the Cardiff clash needing victory to complete a first four-from-four November Tests clean sweep after seeing off Scotland, Australia and Tonga earlier this month.
"What has built nicely is the momentum," said Gatland, who has replaced unavailable full-back Leigh Halfpenny with Liam Williams for the Springboks encounter.
"The players are fully aware of what they've achieved and they can do something special, and from that they know the momentum is created for the Six Nations and they can continue to build towards the World Cup.
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"There is some real maturity in this group, and they are calm. You can see they are motivated as well."
Halfpenny misses the Springboks game due to the concussion he suffered during Wales' 9-6 victory against Australia, with Williams the solitary change from that match.
Halfpenny went off near the end of the Wallabies fixture after being clattered by a challenge from centre Samu Kerevi, who escaped sanction.
Williams, who lined up on the wing and scored two tries when Wales beat Tonga 74-24 last weekend, started twice at full-back for his country last season and in all three 2017 British and Irish Lions Tests against New Zealand.
Gareth Anscombe will fill the fly-half berth, with Dan Biggar on replacement duty, while Adam Beard is again captain Alun Wyn Jones' second-row partner.
Elsewhere, wing George North has recovered from a leg injury that forced him off against the Wallabies and Gatland retains a back row of Dan Lydiate, Justin Tipuric and Ross Moriarty.
South Africa have won plaudits for their vastly improved performances under head coach Rassie Erasmus, who was only appointed to the role eight months ago.
And Gatland added: "They have reclaimed some of their old identity and what they are about.
"Physicality and a strong scrum, a driving lineout and strong ball-carriers. That's why you always respect them for what they are."
Wales team: Liam Williams, George North, Jonathan Davies, Hadleigh Parkes, Josh Adams, Gareth Anscombe, Gareth Davies, Ross Moriarty, Justin Tipuric, Dan Lydiate, Alun Wyn Jones (capt), Adam Beard, Tomas Francis, Ken Owens, Nicky Smith. Reps: Elliot Dee, Rob Evans, Dillon Lewis, Cory Hill, Ellis Jenkins, Tomos Williams, Dan Biggar, Owen Watkin.
