Ireland have drafted Ulster's Craig Gilroy and Simon Zebo of Munster into their extended Six Nations squad.
The wings come in as Ireland await news on Munster's Keith Earls, who will have a scan on a knee injury sustained in Sunday's win over Edinburgh.
A number of players reported to training on Monday with knocks, but none are considered injury concerns.
Ireland start their Six Nations campaign against Scotland at the Aviva Stadium on 2 February.
Lions wing Zebo has found fitness after a foot injury sustained in October while Gilroy has recovered after suffering a suspected concussion in Ulster's victory over Montpellier in the Heineken Cup on 10 January.
Earls was forced off after sustaining his injury in the first half of the Heineken Cup victory over the Scots at Thomond Park.
Lions wing Zebo came on as his replacement and scored Munster's fifth try in the 38-6 win, which secured a home quarter-final against Toulouse.
Ireland coach Joe Schmidt is not short of wing options with Fitzgerald, Dave Kearney, Fergus McFadden and Andrew Trimble all part of the 44-man Six Nations squad announced last week.
Ulster's Tommy Bowe could also come into contention for a Six Nations spot as he nears full fitness after a groin injury.
Ireland extended 46-man squad for Six Nations: Forwards: Rodney Ah You (Connacht)*, Stephen Archer (Munster), Rory Best (Ulster), Robin Copeland (Cardiff Blues)*, Sean Cronin (Leinster), Robbie Diack (Ulster)*, Cian Healy (Leinster), Jamie Heaslip (Leinster), Iain Henderson (Ulster), Chris Henry (Ulster), Rob Herring (Ulster)*, David Kilcoyne (Munster), Mike McCarthy (Leinster), Jack McGrath (Leinster), Martin Moore (Leinster)*, Jordi Murphy (Leinster)*, Paul O'Connell (Munster), Tommy O'Donnell (Munster), Peter O'Mahony (Munster), Mike Ross (Leinster), Rhys Ruddock (Leinster), Devin Toner (Leinster), Dan Tuohy (Ulster), Damian Varley (Munster).
Backs: Isaac Boss (Leinster), Darren Cave (Ulster), Gordon D'Arcy (Leinster), Keith Earls (Munster), Luke Fitzgerald (Leinster), Robbie Henshaw (Connacht), Paddy Jackson (Ulster), Felix Jones (Munster), David Kearney (Leinster), Rob Kearney (Leinster), Ian Keatley (Munster), Ian Madigan (Leinster), Kieran Marmion (Connacht), Luke Marshall (Ulster), Fergus McFadden (Leinster), Conor Murray (Munster), Brian O'Driscoll (Leinster), Eoin Reddan (Leinster), Jonathan Sexton (Racing Metro 92), Andrew Trimble (Ulster), Craig Gilroy (Ulster), Simon Zebo (Munster)
* - Uncapped