Steve Hansen's World Cup trump card could be on show for the All Blacks in Wellington when Beauden Barrett starts a Test at fullback for the first time in six years.
Celebrated five-eighth Barrett will wear No.15 against the Springboks on Saturday in an intriguing tactical switch, with Richie Mo'unga handed playmaker duties.
Hansen has retained just three starting players from the team who opened the Rugby Championship with a nervous 20-16 win over Argentina in Buenos Aires.
One of them is Barrett and another Ben Smith, who also changes position, from fullback to wing, to cater for the seismic change. Lock Brodie Retallick is the lone forward retained.
Crusaders star Mo'unga has been handed comfortably his biggest assignment, having started just two of nine Tests in his rookie international season last year.
His commanding displays for the Super Rugby three-time defending champions had sparked a call for more Test opportunities.
Critics say the free-running Barrett is an inferior game manager and should return to fullback, where he shone as a junior before spending his early Test years from 2012-15 as a game-breaking reserve, often injected at the back.
After replacing the retired Dan Carter at No.10, Barrett was honoured as World Player of the Year in 2016 and 2017.
In 74 Tests, Barrett has started twice at fullback, most recently against Japan in 2013.
Assistant coach Ian Foster said they felt confident 25-year-old Mo'unga was ready to prove his mettle.
"He's just had more experiences out in the middle," Foster said.
"I love the way he's dealt with leading a Super team that were the defending champions. He dealt with the pressures of that and help guide them significantly to another one."
The All Blacks are close to full strength in most areas, having named three centurions in the pack, including skipper Kieran Read.
However, No.8 Read is the only proven force in an experimental loose forward mix, with gun flankers Sam Cane and Ardie Savea omitted.
Matt Todd and Shannon Frizell get rare starts on the side of the scrum while Dalton Papali'i and Vaea Fifita are bench options.
Another with plenty to prove is injury-plagued inside centre Sonny Bill Williams, whose World Cup selection is far from certain after managing to start just five Super Rugby games for the Blues.
Duane Vermeulen will lead an overhauled Springboks team to face the All Blacks in their Rugby Championship Test in Wellington on Saturday.
As expected, coach Rassie Erasmus has changed his starting team almost entirely from that which beat the Wallabies 35-17 in Johannesburg.
Twelve of the run-on XV are players who arrived in New Zealand last week to begin preparations to face the world champions.
The three players retained to start are winger Makazole Mapimpi, flanker Pieter-Steph du Toit and lock Eben Etzebeth.
The bench comprises seven players from last week's game, along with lock RG Snyman, who lost a battle with Etzebeth for a starting berth.
Six of the 23-man squad are offshore-based players including four starters - fullback Willie le Roux (Toyota Verblitz), winger Cheslin Kolbe (Toulouse), halfback Faf de Klerk (Sale) and lock Franco Mostert (Gloucester).
Le Roux and Kolbe both scored tries in last year's 36-34 upset of New Zealand in Wellington, with le Roux also spending a stint in the sin bin during the dramatic final minutes.
Earning the captaincy is a milestone for respected No.8 Vermeulen, the 46-Test veteran who hasn't played a Rugby Championship Test for five years.
His Springboks career was in doubt when he left the Stormers for contracts in France and Japan following the 2015 World Cup.
The 33-year-old returned to the Stormers last year and played seven Tests although he missed the entire Rugby Championship with injury.
Erasmus said Vermeulen's appointment was about building a group of leaders within his squad heading to the World Cup.
"It is important that we continue to build on our leadership for this important year, especially while our regular skipper, Siya Kolisi, is out of action because of injury rehabilitation," Erasmus said.
"Duane is an experienced captain and we have a strong group of leaders in the team, which includes Eben Etzebeth and Pieter-Steph du Toit, who have both captained the Springboks before, as well as a number of other franchise captains."
New Zealand hosts South Africa at Westpac Stadium, Wellington, on Saturday July 27, kicking off at 7:35pm local, 5;35pm AEST, LIVE on FOX SPORTS and Kayo Sports.
New Zealand to face South Africa
1. Joe Moody (37)
2. Codie Taylor (41)
3. Owen Franks (106)
4. Brodie Retallick (76)
5. Samuel Whitelock (108)
6. Shannon Frizell (4)
7. Matt Todd (17)
8. Kieran Read - captain (118)
9. TJ Perenara (55)
10. Richie Mo'unga (9)
11. Rieko Ioane (24)
12. Sonny Bill Williams (51)
13. Jack Goodhue (7)
14. Ben Smith (77)
15. Beauden Barrett (74)
16. Dane Coles (61)
17. Ofa Tuungafasi (27)
18. Angus Ta'avao (4)
19. Vaea Fifita (10)
20. Dalton Papalii (2)
21. Aaron Smith (83)
22. Anton Lienert-Brown (34)
23. George Bridge (1)
South Africa to face New Zealand
1. Steven Kitshoff
2. Malcolm Marx
3. Frans Malherbe
4. Eben Etzebeth
5. Franco Mostert
6. Kwagga Smith
7. Pieter-Steph du Toit
8. Duane Vermeulen (capt)
9. Faf de Klerk
10. Handre Pollard
11. Makazole Mapimpi
12. Damian de Allende
13. Lukhanyo Am
14. Cheslin Kolbe
15. Willie le Roux
16. Bongi Mbonambi
17. Tendai Mtawarira
18. Trevor Nyakane
19. RG Snyman
20. Francois Louw
21. Herschel Jantjes
22. Frans Steyn,
23. Jesse Kriel.