Ireland will be without both Jonathan Sexton and Robbie Henshaw for their final November Test against Australia next weekend.
Sexton and Henshaw picked up their respective injuries in the first half of Saturday's 21-9 defeat to New Zealand.
Henshaw was stretchered off after an 11th-minute tackle from Sam Cane left him concussed, while Sexton was withdraw with a hamstring problem.
CJ Stander also left the field with suspected concussion, joining Rob Kearney (concussive symptoms), Simon Zebo (cramp) and Tadhg Furlong (dead leg) in the Irish treatment room.
Ulster centre Stuart Olding and uncapped Munster utility back Rory Scannell have been called up to bolster Joe Schmidt's squad.
Team manager Michael Kearney said: "Robbie Henshaw was knocked unconscious by a shoulder contact to his jaw. He suffered a concussion and will not be involved this week.
"Johnny Sexton has suffered a minor hamstring injury and has been ruled out of the game at the weekend.
"Rob Kearney developed concussive symptoms after the game and following assessment. He will follow the graduated return-to-play protocols.
"CJ Stander was removed for a suspected concussion and will complete the HIA [head injury assessment] process and the return-to-play protocols."