South Africa make 14 changes for second Test against Wales
Nienaber has named a fresh-looking side that includes two uncapped players in outside back Kurt-Lee Arendse and number eight Evan Roos.
Leicester-bound World Cup-winner Handre Pollard returns at fly-half in place of the out-of-form Elton Jantjies and takes over the captaincy from Siya Kolisi.
Former world player of the year Pieter-Steph du Toit is also back in the team after recovering from a shoulder injury.
Hooker Malcolm Marx, prop Vincent Koch and utility back Damian Willemse are the only other players who were involved last week to be included in the latest squad, with all three named among the replacements.
Prop Ntuthuko Mchunu, lock Ruan Nortje, utility forward Deon Fourie and scrum-half Grant Williams are further potential debutants from the bench.
Strike a balance
Nienaber said: “We said from the outset that we needed to strike a balance between giving our talented young players an opportunity to show what they can do at international level, and winning.
“If one looks at the balance between players who have played at this level and those who have performed consistently well for their franchises and clubs, I think we have a nice balance in this squad.
“Wales showed last week that they are fighters and can go for the full 80 minutes and we are expecting nothing different from them this week.
“This will certainly be a good test for the younger players in the group to measure themselves against some of the best players in Wales.”
Wales pushed the world champions hard in a thrilling contest last week only to be beaten by a Willemse penalty from the final kick of the game.
Nienaber said: “Wales will certainly gain confidence from their performance last week, and I have no doubt they will feel aggrieved by the fact that they lost out so narrowly, so we know we have to produce a top-class performance to win this weekend.
“They are a team that keep going until the final whistle, so we expect them to push us to the limit, but we know what our standards are as a team, and every player knows what is expected of him.
“It is definitely going to take a full 80-minute effort to win the match and, if we do well, hopefully the result will take care of itself.”
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