"I spoke to Jesse a couple of weeks ago and he seems to think he's going to be ok to play," said Maguire.
"Obviously when you're having a baby you can't judge exactly when that is. I'll keep chatting with him but as far as I am aware he's looking forward to playing.
"I know he's really keen to get back into the jersey and I know he's going to do everything possible to ensure he's there.
"But family does come first and you've got to look after everyone at home but I know he'll do everything possible."
Maguire was keeping his cards close to his chest regarding potential leaders as he waits to discuss the matter with the side's senior players once the squad assembles in Auckland on Saturday.
Blair was initially set to lead the Kiwis as their un-official captain for the midseason test loss to England in Denver before the Warriors veteran was ruled out through suspension.
First-choice hooker Issac Luke helped guide the side in Blair's absence at Mile High Stadium but is unavailable as he awaits shoulder surgery, with knee injuries also ruling out Warriors captain Roger Tuivasa-Sheck and second-rower Tohu Harris.
"I want to get the senior group together and I'm going to talk to those boys around that," said Maguire.
"I've got a few thoughts myself but I want to have a chat to a few of the senior guys that I've got in the crew.
"Ultimately it's building the team around that group of players and I want a few opinions from those boys as well."
One player is still to be added to the squad as Maguire considers his options after both Melbourne prop Nelson Asofa-Solomona (high ankle sprain) and Roosters interchange forward Zane Tetavano (bicep) suffered injuries in Sunday's NRL grand final.
Maguire is looking at choosing another big body with Melbourne's Sam Kasiano and uncapped Warriors front-rower Bunty Afoa both in the selection frame.
"Sam Kasiano is one that's been playing and performing at Melbourne and Bunty Afoa and some other guys too that we're looking at," he said.
Roosters centre Joseph Manu, Storm backline utility Jahrome Hughes, Penrith second-rower Corey Harawira-Naera, and 20-year-old Warriors second-rower Isaiah Papali'i are the other newcomers in the side.
Papali'i may drop out of the squad and captain the Junior Kiwis in their curtain-raiser clash against the Junior Kangaroos but will be on deck for the away tests.
"There's a fair chance he may. I'll have a look at the squad when they come in and Isaiah could possibly be the captain of that team if he goes back and plays."
