A Rugby Championship campaign that has gone pear-shaped for South Africa means great significance is being attached to the final-round clash with Argentina in Durban on Saturday.

“This will be a massive Test for us,” admitted Springboks coach Heyneke Meyer as he looked ahead to a showdown that will decide who finishes bottom of the standings.

Australia and title-holders New Zealand have nine points each ahead of a Sydney title decider earlier on Saturday, South Africa a paltry two from losing bonus points and Argentina none.

The 2015 Springboks have become the team that cannot put a game to bed, conceding late tries in Brisbane and Johannesburg to fail against the Wallabies and All Blacks.

“We will never accept that we lost our last two Tests,” stresses 47-year-old Meyer, who has won 26 Tests, lost 11 and drawn two since taking charge of the green and gold three seasons ago.

“On both occasions we were in positions to win and let them slip.”

Peter de Villiers, who was succeeded as South Africa coach by Meyer, blames overweight Springboks for the fade-outs.

“We need to address the fighting-fit weight of the players so that they can last for 80 minutes,” he says.

“The players are carrying excess unnatural weight which is why we cannot maintain intensity for full matches.

“I believe we bulk up our Springboks instead of making them match-fit.”

Although the Springboks have been much more impressive than fellow strugglers the Pumas in the first two Championship rounds, Meyer is wary of the Argentines.

This could partly be due to the closeness of the games last year with the Springboks winning only 13-6 at home in monsoon-like conditions and scraping a fortunate 33-31 away victory.

“It is going to be tough because the Pumas are coming for us, as they have done during the past three seasons,” conceded Meyer.

“This is going to be a great challenge for the Springboks and I cannot wait for the kick-off.”

After losing both Tests this season and four of the last six, Meyer shelved reported plans to start with little-used utility back Patrick Lambie and fly-half Morne Steyn, and almost-fit scrum-half Fourie du Preez.

Of the three starting line-up changes to the side beaten 27-20 by New Zealand, two were forced with tighthead prop Jannie du Plessis and flanker Francois Louw injured.

South African find-of-the-season Jesse Kriel moves from outside centre to the right wing to accommodate skipper Jean de Villiers, back in the starting line-up nine months after reconstructive knee surgery.

The reshuffle means winger Cornal Hendricks drops out of the matchday 23, and in the pack Vincent Koch comes in for Du Plessis and Marcell Coetzee replaces Louw.

Argentina coach Daniel Hourcade has reacted to a generally poor performance when losing 34-9 at home against Australia by making 11 changes, one injury-enforced.

Veteran play-anywhere back Juan Martin Hernandez makes his season debut in place of fly-half Nicolas Sanchez, the leading 2014 Championship points scorer but an underperformer this season.

Only two Pumas, skipper and hooker Agustin Creevy and loosehead prop Marcos Ayerza, have been chosen to start all three Championship Tests.

The odds lean heavily toward a Springboks victory as they have won all eight previous Tests against the Pumas in the republic.