Ulster duo Paul Marshall and Craig Gilroy are among six players called into the Ireland squad for this week's two-day training camp in Kildare.
Marshall replaces injured Eoin Reddan (leg) with Gilroy taking over from Munster's Simon Zebo (ankle).
Gordon D'Arcy's absence because of rib damage means uncapped Munster centre James Downey will join the squad.
Ronan O'Gara (dead leg) is replaced by Ian Madigan with Ronan Loughney in for Ulster prop Declan Fitzpatrick.
Fitzpatrick is continuing rehab on a knee injury while Loughney's Connacht team-mate Mike McCarthy will miss the get-together because of a calf strain and is replaced by Leinster's Devin Toner.
Uncapped Ulster duo Iain Henderson and Luke Marshall were among the notable inclusions in the original 33-strong squad announced for the camp.
The training camp is taking place at Carton House in county Kildare as part of the build-up towards Ireland's autumn internationals.
Ireland face South Africa at the Aviva Stadium on 10 November before taking on Argentina two weeks later.