Colin Slade should start for the All Blacks on Sunday, and he will most probably be served by his so-called rival.
Slade was named as Dan Carter's back-up in the squad and it would be a long shot for the selectors to disregard that and go with Piri Weepu.
They also have the assurance of having Weepu on the field, as he will wear the No 9 jersey on Sunday night against Argentina.
Jimmy Cowan has slipped in the pecking order and Andy Ellis is believed to offer more in coming off the bench and slotting into the halfback position.
Skipper Richie McCaw will take his place on the openside flank and, with Kieran Read successfully getting through his first match back last Sunday, the preferred loose forward trio will finally get a run at this tournament. Jerome Kaino goes from strength to strength and his presence will undoubtedly help the All Black forward pack which will strike a fired-up Pumas front eight.
Adam Thomson might have been overtaken in the loose forward reserves by Victor Vito, especially with the Otago man missing last week's game because of an ankle worry.
With Carter sidelined, the way has now been opened up for Mils Muliaina to play his 100th test for the All Blacks.
It would be unlikely Aaron Cruden will come straight on to the bench after only joining the squad this week, so Muliaina will probably get a spot as a back reserve, alongside Sonny Bill Williams and Ellis.
There are no major injury concerns. Zac Guildford is the only player not available for selection, because of a tight hamstring, but he would have not made the 22-man squad anyway.
Veteran lock Ali Williams has been putting pressure on Sam Whitelock with some impressive efforts but Whitelock's athleticism and energy will keep him in the side.
The side is named this morning by coach Graham Henry and the Argentinian side is to be named later today.
All Blacks
Possible team
Israel Dagg, Cory Jane, Conrad Smith, Ma'a Nonu, Richard Kahui, Colin Slade, Piri Weepu, Kieran Read, Richie McCaw (captain), Jerome Kaino, Sam Whitelock, Brad Thorn, Owen Franks, Keven Mealamu, Tony Woodcock.
Reserves: Andrew Hore, Ben Franks, Ali Williams, Victor Vito, Andy Ellis, Sonny Bill Williams, Mils Muliaina.