Confirming Fergus McFadden's absence for the All Blacks game and the extent of Kearney's injury, Ireland team manager Michael Kearney said: "Fergus has unfortunately fractured the fifth metacarpal in his right hand. He'll be sidelined for a number of weeks.
"Rob suffered a blow to the ribs and has a subluxed costal cartilage. This was very painful at the time and is improving well but he won't train for the early part of the week.
"It is very much a day-to-day injury and is hard to tell at this stage whether he will be available to play Sunday."
Munster full-back Felix Jones has been called up to the squad to provide cover as has Ulster's Darren Cave, who Kearney said will add 'a bit of flexibility to training this week' with Brian O'Driscoll nursing a tight calf.
Meanwhile, the hamstring injury that forced out-half Jonathan Sexton off at half-time in the defeat to Australia continues to threaten his participation against New Zealand.
Kearney confirmed: "Johnny pulled up with a suspected hamstring strain, he was scanned on Saturday night and the results were less worrying than initially feared. He has already begun intensive rehabilitation and like Rob will be monitored on a daily basis.
"In terms of his chances of been ready for Sunday, the only thing I can say at this stage is that he hasn't been ruled out.
"I'd say that Joe (Schmidt) would like them to train by Friday, but Rob and Johnny are two world class players and I think that Joe will give them every chance he can to have them ready on Sunday."
Regarding his own calf issue, O'Driscoll is confident that he will be back close to full fitness for Sunday's showdown as he gears up for one final crack at the All Blacks.
"I would be pretty positive (about the injury). I've been unfortunate this year that I've had a few niggly things and this calf has slowed me down a little bit," explained the 127-times capped centre.
"I got it at training and it kept me out for longer than I thought. It has just stayed with me a little bit. I could feel it at the weekend a bit but I managed to see out the game.
"But there are lots of times I haven't played at 100% fitness and all going well, if I handle the week well I shouldn't be far off 100% come the weekend."