A squad to contest the Oceania Cup in Stratford later in October will be chosen after the Argentine series - with players from a national development group also in the frame for that - then there's the World League final in December in Argentina on the horizon.
The least experienced player in the national squad is Central goalkeeper Georgia Barnett, with 16 international appearances. The average age of the players is 23.
She'll get plenty of game time against Argentina as senior keeper Sally Rutherford is playing in the Australian league.
Former captain Kayla Whitelock and New Zealand's most capped international, defender Emily Naylor, are predictably recalled after taking a year off since the Commonwealth Games.
Hager was delighted with Naylor's form during last week's national league in Whangarei but will take his time getting Whitelock back on the field.
''Kayla showed some signs, but is a little way off yet. We didn't want to risk her and may not for rest of the year," Hager said.
He expects Whitelock will return to the captaincy once back in action, rating her a top class leader whom the other players respect.
The fourth-ranked Black Sticks will face world No 2 Australia at the Oceania Cup and Hager said the door is open for selection from within the development group as well.
''We haven't closed the door (on anyone outside) the 24. We're picking it from the whole group," Hager said.
He was delighted with the standard of hockey in the national league.
''It's one of the best tournaments I've seen. Most games were very competitive and there were some very good performances."
New Zealand will play Argentina in Blenheim, Nelson and Christchurch from October 3-11.
New Zealand women's hockey squad:
Goalkeepers: Georgia Barnett (Central), Amelia Gibson (Auckland), Sally Rutherford (Midlands)
Defenders: Natasha Fitzsimons, Rose Keddell (Midlands), Pippa Hayward (Canterbury), Kathryn Henry (North Harbour), Emily Naylor (Central), Brooke Neal (Northland), Liz Thompson (Auckland), .
Midfielders: Sam Charlton, Gemma Flynn (Midlands), Jordan Grant (Canterbury), Ella Gunson, Stacey Michelsen (Northland), Julia King (Auckland), Anita Punt (Capital), Kayla Whitelock (Central), Petrea Webster (North Harbour).
Attackers: Sophie Cocks, Olivia Merry (Canterbury), Katie Glynn, Charlotte Harrison (Auckland), Kirsten Pearce (North Harbour).
Squad to play Argentina: Barnett, Charlton, Cocks, Maddie Dowe (Auckland), Fitzsimons, Flynn, Gibson, Shiloh Gloyn (Midlands), Hayward, Harrison, Henry, Keddell, Rachel McCann (Canterbury), Merry, Naylor, Pearce, Punt, Kelsey Smith (Capital), Thompson, Webster.
