James Ryan will miss Ireland's final Six Nations match against Scotland on Saturday.
The Leinster lock sustained a head injury early on in Saturday's defeat of England at Twickenham.
England's Charlie Ewels was sent off after just 82 seconds of the game for the challenge which resulted in Ryan being withdrawn.
He's going through the return to play protocols but won't be considered for this weekend's match.
Ryan Baird has also been ruled of the final game of the tournament due to a back issue.
Andy Farrell has called up Leinster duo Ross Molony and Joe McCarthy to train with the squad.
Ulster trio Robert Baloucoune, Nick Timoney and Mike Lowry have all returned to the squad, having featured in their win over Leinster in the United Rugby Championship on Saturday.
Ireland will win the Triple Crown if they beat Scotland at the Aviva Stadium on Saturday, but will require a slip-up from France against England to be in with a chance of winning the championship.
Preparations have begun for the game, with the squad having reassembled at their Carton House base last night.
Ireland squad vs Scotland
Backs (16)
Bundee Aki (Connacht/Galwegians) 36 caps
Robert Baloucoune (Ulster/Enniskillen) 2 caps
Joey Carbery (Munster/Clontarf) 31 caps
Jack Carty (Buccaneers/Connacht) 11 caps
Craig Casey (Munster/Shannon) 5 caps
Andrew Conway (Munster/Garryowen) 30 caps
Jamison Gibson Park (Leinster) 16 caps
Mack Hansen (Connacht) 3 caps
Robbie Henshaw (Leinster/Buccaneers) 56 caps
James Hume (Ulster/Banbridge) 3 caps
Hugo Keenan (Leinster/UCD) 19 caps
James Lowe (Leinster) 11 caps
Michael Lowry (Ulster/Banbridge) 1 cap
Conor Murray (Munster/Garryowen) 95 caps
Garry Ringrose (Leinster/UCD) 41 caps
Johnny Sexton (Leinster/St Mary’s College) 104 caps CAPTAIN
Forwards (19)
Finlay Bealham (Connacht/Buccaneers) 22 caps
Tadhg Beirne (Munster/Lansdowne) 29 caps
Jack Conan (Leinster/Old Belvedere) 26 caps
Gavin Coombes (Munster/Young Munster) 2 caps
Caelan Doris (Leinster/St Mary’s College) 16 caps
Tadhg Furlong (Leinster/Clontarf) 56 caps
Cian Healy (Leinster/Clontarf) 115 caps
Dave Heffernan (Connacht/Buccaneers) 6 caps
Iain Henderson (Ulster/Academy) 67 caps
Rob Herring (Ulster/Ballynahinch) 25 caps
Dave Kilcoyne (Munster/UL Bohemians) 47 caps
Jeremy Loughman (Munster/Garryowen) uncapped
Joe McCarthy (Leinster/Dublin) uncapped
Ross Molony (Leinster/UCD) uncapped
Peter O’Mahony (Munster/Cork Constitution) 83 caps
Dan Sheehan (Leinster/Lansdowne) 6 caps
Nick Timoney (Ulster/Banbridge) 2 caps
Kieran Treadwell (Ulster/Ballymena) 4 caps
Josh van der Flier (Leinster/UCD) 39 caps