Robbie Henshaw will miss Ireland's Six Nations clash with France on Sunday.
The Ireland back has been ruled out through injury after his recovery from a dead leg took longer than anticipated.
Joe Schmidt had given Henshaw every chance to prove his fitness, taking the unusual step of delaying confirmation of his squad until this morning, but Sunday's game will come too soon for Henshaw.
The Leinster star has not featured since Ireland's 32-20 opening-round defeat to England, where he was deployed at full-back for just the second time in his Test career.
Sean Cronin has been dropped from the 37-man squad just a week after his first Six Nations start in 68 international appearances.
The 32-year-old has been replaced by Ulster hooker Rob Herring, who will compete with captain Rory Best and Niall Scannell for the position.
There was better news for Joey Carbery, however, as the fly-half's recovery from a hamstring injury has progressed well enough to see him included.
Last week, Schmidt said if Carbery can train on Wednesday and Friday, he'll be considered for the squad to play France. The head coach has decided to add extra cover for the position, though, with Ross Byrne joining Johnny Sexton, Carbery, and Jack Carty in the squad.
Connacht scrum-half Kieran Marmion returns from injury to take his place in the squad ahead of his provincial teammate Caolin Blade. Garry Ringrose, CJ Stander, Jordan Larmour, and Tadhg Beirne are all passed fit after missing the win over Italy.
Back-row Dan Leavy misses out, although his comeback from a calf injury continues to move closer. He will continue to increase his running volume outside of team training this week.
Schmidt will name his matchday-23 on Friday.
Rory Best (Banbridge/Ulster) 115 caps (c)
Tadhg Beirne (Lansdowne/Munster) 4 caps
Jack Conan (Old Belvedere/Leinster) 12 caps
Ultan Dillane (Corinthians/Connacht) 13 caps
Tadhg Furlong (Clontarf/Leinster) 31 caps
Cian Healy (Clontarf/Leinster) 86 caps
Iain Henderson (Queens University/Ulster) 43 caps
Rob Herring (Ballynahinch/Ulster) 7 caps
Dave Kilcoyne (UL Bohemians/Munster) 27 caps
Jack McGrath (St Marys College/Leinster) 54 caps
Jordi Murphy (Lansdowne/Ulster) 27 caps
Sean O’Brien (UCD/Leinster) 55 caps
Peter O’Mahony (Cork Constitution/Munster) 55 caps (vc)
Andrew Porter (UCD/Leinster) 13 caps
Quinn Roux (Galwegians/Connacht) 11 caps
Rhys Ruddock (Lansdowne/Leinster) 21 caps
James Ryan (UCD/Leinster) 15 caps
John Ryan (Cork Constitution/Munster) 17 caps
Niall Scannell (Dolphin/Munster) 12 caps
CJ Stander (Shannon/Munster) 29 caps
Josh van der Flier (UCD/Leinster) 16 caps
Bundee Aki (Galwegians/Connacht) 15 caps
Ross Byrne (UCD/Leinster) 2 caps
Joey Carbery (Clontarf/Munster) 18 caps
Jack Carty (Buccaneers/Connacht) 1 cap
Andrew Conway (Garryowen/Munster) 11 caps
John Cooney (Terenure College/Ulster) 7 caps
Keith Earls (Young Munster/Munster) 75 caps
Chris Farrell (Young Munster/Munster) 5 caps
Tom Farrell (Coolmine/Connacht) 0 caps
Rob Kearney (UCD/Leinster) 89 caps
Jordan Larmour (St Mary’s College/Leinster) 11 caps
Kieran Marmion (Galwegians/Connacht) 24 caps
Conor Murray (Garryowen/Munster) 70 caps
Garry Ringrose (UCD/Leinster) 18 caps
Jonathan Sexton (St Marys College/Leinster) 81 caps (vc)
Jacob Stockdale (Lurgan/Ulster) 17 caps