Phelan said he had called on 15 domestic players from Argentina's local rugby force - to give them experience and rest his bigger names for the August Rugby Championship debut.
Among the four World Cup survivors are veteran 35-year-old prop Rodrigo Roncero and the equally veteran first five-eighths Felipe Contepomi, 34 - the former a terrific servant of Pumas rugby and the latter still a playmaker and driving force behind the team. There are nine European-based players in the squad - though generally from lesser clubs.
Roncero, who played for Stade Francais, announced last month he would not renew his contract at the end of the season. Roncero has played 48 tests for the Pumas, appearing at three World Cups as part of Argentina's formidable front row alongside current Stade Francais forwards coach Mario Ledesma and Martin Scelzo.
Other World Cup squad players in Phelan's initial 29-man squad are loose forwards Julio Farias Cabello and Leonardo Senatore.
An example of the struggle the Pumas face with gaining access to overseas-based players came when first five/fullback Ignacio Mieres re-signed with British club Exeter recently. In spite of new rules allowing players to be released for the international window, the contract extension hit trouble when it came to the issue of potential international call-ups, especially for the newly-formed Rugby Championship.
Mieres, 25, has only played four times for the Pumas and was the substitute for Dan Carter at Perpignan when the latter's ill-fated sabbatical from All Black rugby was interrupted by a serious injury in 2009.
"I'm really happy to have signed because I always said I wanted to stay at Exeter," explained Mieres. "I knew it was a difficult contract because of the situation with Argentina, but after lots of talks both parties are happy with the contract.
"Right now it's an extraordinary situation because no one has ever experienced the competition and it's the first year. As I said, I wanted to stay here and [head coach] Rob [Baxter] wanted to keep me here, so I'm really happy the club - who have been great throughout - have decided to keep me and not oppose any call-up I may get from Argentina."
- Agencies