"It is a reflection of how good a player he is,"said Hansen on why Dagg was selected. "We felt that Waisake [Naholo] needed a game in Chicago and Izzy had a busy season.
"If you were picking the best team every week and you had everyone physically and mentally fresh, Izzy would play every week. But that's not the nature of the beast is it? This is the 13th test and we have gone around the world twice in the last six, seven weeks and people aren't mentally and physically fresh so you have to give people opportunities to have a breather.
"He [Dagg] got one in Chicago and maybe it wasn't the right time to give him one but then maybe he would have needed one this week. You have got to roll the dice and you have got to back the people you have got."
On the subject of backing people, Hansen went to some length to shoot down anyone who has suddenly gone cold on Beauden Barrett.
The recently crowned world player of the year has had a magical season where his game management has improved out of sight and supported his electric and eclectic range of skills.
He has been mostly brilliant, but like just about every other All Black, he didn't play well in Chicago. Hansen's expectation is that if the blokes wearing jersies one to eight get their game sorted on Saturday, it will provide the platform for Barrett to deliver the sort of performances that have made him such an influential figure.
"We have all the confidence in the world in Barrett," said Hansen. "His last performance he missed two kicks and Crudes has missed two kicks when he has played and last week he kicked really well against Italy. It is about what we want and how we want to play and both of them are good enough to start.
"But we just think that Beauden is playing well. Like most of the team in Chicago, they didn't have a great day out and he didn't have one. But you would expect all of that group to play better. Whether that is good enough for us to win the match or not, we will have to wait and see. If we had talked about playing Cruden a couple of weeks ago everyone would have said we were stupid. Now because we have lost one game everyone thinks Barrett should get chopped.
"It's the old story isn't it - the people who have to make the decisions are the ones who will be judged and everyone else's ideas don't get challenged they don't get to see them happen because if they are not the same as ours, they don't happen.
"We have got a lot of confidence in Beauden and a lot of confidence in Crudes and both of them will get game time I am sure."
All Blacks squad to face Ireland (with Test caps in brackets):
1. Joe Moody (22)
2. Dane Coles (47)
3. Owen Franks (88)
4. Brodie Retallick (58)
5. Samuel Whitelock (82)
6. Liam Squire (7)
7. Sam Cane (39)
8. Kieran Read - captain (95)
9. Aaron Smith (56)
10. Beauden Barrett (47)
11. Julian Savea (50)
12. Anton Lienert-Brown (6)
13. Malakai Fekitoa (22)
14. Israel Dagg (59)
15. Ben Smith (59)
16. Codie Taylor (13)
17. Wyatt Crockett (56)
18. Charlie Faumuina (44)
19. Scott Barrett (2)
20. Ardie Savea (10)
21. TJ Perenara (27)
22. Aaron Cruden (45)
23. Waisake Naholo (10)
