Ireland duo Garry Ringrose and Iain Henderson have been ruled of Saturday’s Grand Slam decider with England.
Centre Ringrose was stretchered off in the closing stages of Sunday’s win over Scotland with a head injury while second row Henderson will undergo surgery on a broken arm.
Hookers Dan Sheehan and Ronan Kelleher will be monitored following shoulder injuries in a bruising encounter.
Back row Caelan Doris’ hip injury will be assessed ahead of the final game.
The IRFU has said Ringrose is “doing well” and has returned to Dublin after a nasty collision when attempting to tackle Blair Kinghorn at Murrayfield.
Injury-hit Ireland lost five players against Scotland but ran out 22-7 winners despite playing the majority of the second half with no hooker and three props on the pitch.
Veteran prop Cian Healy played in the role in the scrums while flanker Josh van der Flier threw into the line-out after replacement hooker Kelleher was forced off early in the second half, having earlier come on for Sheehan.
Ulster hooker Tom Stewart has been added to the squad as cover for Sheehan and Kelleher, while uncapped Leinster second row Ross Molony has also been included.
Ireland can win a first Grand Slam under head coach Andy Farrell if they defeat England in Dublin on Saturday.