For excluded players like halfbacks TJ Perenara and Brad Weber, there would be chances to impress with the Māori All Blacks, who have two games against Ireland.
Fox, whose stint as selector ends with the Ireland series, said discussions around the selections this year had been more involved than in his previous seasons in the role, back to 2012.
"Part of that is off the last two games of the year , the pressure we got put under, looking at not only what we are doing with our game, but the athletes we think we need to win and play the game we want, to combat what the opposition is going to throw at us.
"That's why those long discussions have happened, and why we've come up with the group we have," he said.
Fox added that there were still chances for young players who, if they continued the development they showed in Super Rugby Pacific this year, could still push for inclusion in next year's Rugby World Cup side.
He wasn't surprised that former league star Roger Tuivasa-Sheck had made a smoother transition to rugby than most others who changed codes.
"Roger came from a rugby background at school, so there's a little still there. He's a great professional. He's done his homework and diligently gone about his work.
"It's as much about the work he's doing off the field to get his growth. It [his selection] hasn't relied on his natural talent, and we can see his talent anyway. He's got great feet, he'll run that channel really, really well. He's a good reader on defence and makes, for the most part, sound decisions.
"He's a fit man and works hard. There's still a lot more in Roger yet we believe hence part of the reason we've picked him because we want to accelerate that development with an eye towards next year."
Fox said the selectors didn't see him as a project. He was not too far from saying he could be picked, without taking too much risk.
"Yes, there's development still to come, as there is with all players to be fair, but, he's a name that will be talked about for that first Test, and particularly if he happened to have a big game on Saturday night that says 'I can handle this stage', and makes us think a bit more," he said.
Fox said fellow Blues player Stephen Perofeta was dogged by injury for a couple of years and lacked some belief in his abilities. The selectors had talked about him for years, but he had never delivered on his talent until this year.
"He's been a reluctant goal-kicker, but now he's goal-kicking well because he wants to do it rather than reluctantly doing it.
"And I think he has a belief in his talent, finally, to step up and show how good he is. He's benefited from one, the coaching group [at the Blues], but also, the players he's got around him," he said.
Perofeta had silky, smooth moves and was quicker than many people realised, similar in many ways to the former All Black Steven Pokere.
"He's got a great awareness of where a hole is, of where space is. Whether he's got ten on his back or 15, he has vision and great feel for what the opportunity is around him.
"Damian McKenzie's not available and we've always had a guy who can fill that role, and Stephen slots nicely into that," he said.
Fox felt Beauden Barrett had taken his time, as many players did, to adjust to the greater demands of Test rugby after his stint in Japan.
But, back in the All Blacks, he played well, and this year was on top of his game.
"We all know Beauden's talent, we've seen it since 2012. We're lucky we've got some real talent at 10 [first five-eighths]," he said.