The All Blacks' policy around not training is under the microscope after Sonny Bill Williams went down with illness ahead of their Test against the Springboks.
New Zealand are desperate to get first-choice inside centre Williams on the park in what has been a season dogged by injury.
He looked set to return for Saturday's Rugby Championship Test in Wellington after scans showed he had overcome a 10-week shoulder injury.
However, he missed Tuesday's practice session with an ailment and is in doubt to be included in what should be close to New Zealand's strongest team for their final home Test of the year.
The All Blacks have previously said their strong preference is for players to train all week if they are to be considered for match duty.
Williams' last game was the third Test against France on June 23 - his only international appearance of 2018.
The 33-year-old's availability this week would be timely as Ngani Laumape is ruled out with knee damage suffered in Saturday's 46-24 win over Argentina in Nelson.
The All Blacks want to restore their preferred midfield combination of Williams and Ryan Crotty, who has been out for a month following a head knock.
Star winger Rieko Ioane's hamstring is healed and is likely to return, along with match-winning five-eighth Beauden Barrett.
Sam Cane and Liam Squire should be restored as flankers despite some muscular efforts from fringe candidates Ardie Savea and Shannon Frizell against the Pumas.
The tight five may be the only area below full strength for the world champions.
Lock Brodie Retallick (shoulder) and prop Joe Moody (thumb) are poised to miss the rest of the Rugby Championship, while hooker Dane Coles is near the end of a nine-month recovery from a knee injury.
Assistant coach Ian Foster said Coles is targeting a provincial return this month and could yet figure in the final Rugby Championship Test against South Africa in Pretoria on October 7.
"Every week he's getting closer and closer," Foster said.
"It's exciting and he's starting to believe that too I think. He's got that glint in his eye."