Ulster hooker Rory Best and Munster winger Anthony Horgan were added to the Ireland squad for the permanent tsb autumn Tests on Sunday evening.
Best, 23, beat off competition from Munster number 2 Jerry Flannery to replace the injured Frankie Sheahan (neck ligaments) in coach Eddie O'Sullivan's squad.
Leinster's Bernard Jackman, who earned his first two caps as Sheahan's deputy on the Japan tour, unfortunately injured himself against Glasgow in the Heineken Cup on Sunday.
It will be a first involvement in the senior set-up for Best, who went to the 2003 Under-21 World Cup with Ireland. Best has been a vital cog in Mark McCall's Ulster side this season, operating a consistent lineout with Ireland's Matt McCullough and former Wallaby Justin Harrison.
A younger brother of Ulster captain Simon Best, who is one of four props included by O'Sullivan, Best is certain to make the bench for the autumn Test opener against New Zealand on November 12 as Saracens recruit Shane Byrne is the only other hooker in the squad.
Horgan, a try-scorer in Munster's five-try 42-16 Pool One defeat of Castres on Saturday, beefs up the backs contingent with Leinster and Lions speedster Denis Hickie suffering from a dislocated fibula.
Horgan, who turns 29 on November 15, earned his fifth and sixth caps against Japan in June and recently came back from a knee injury.
Llanelli skipper Simon Easterby, who sustained a broken nose last week against Toulouse, is still to pass a fitness test to confirm his place.
IRELAND Squad (31):
Forwards (17): Neil Best (Belfast Harlequins/Ulster), Rory Best (Belfast Harlequins/Ulster), Simon Best (Belfast Harlequins/Ulster), Shane Byrne (Saracens), Reggie Corrigan (Greystones/Leinster), Leo Cullen (Leicester), ** Simon Easterby (Llanelli), Anthony Foley (Shannon/Munster), John Hayes (Bruff/Munster), Jamie Heaslip (Clontarf/Leinster), Marcus Horan (Shannon/Munster), Matt McCullough (Ballymena/Ulster), Denis Leamy (Cork Constitution/Munster), Donncha O'Callaghan (Cork Constitution/Munster), Johnny O'Connor (Wasps), Malcolm O'Kelly (St Mary's College/Leinster), David Wallace (Garryowen/Munster).
Backs (14): Tommy Bowe (Belfast Harlequins/Ulster), Kieran Campbell (Dungannon/Ulster), Gordon D'Arcy (Lansdowne/Leinster), Girvan Dempsey (Terenure College/Leinster), Anthony Horgan (Cork Constitution/Munster), Shane Horgan (Lansdowne/Leinster), David Humphreys (Dungannon/Ulster), Robert Kearney (UCD/Leinster), Kieran Lewis (St Mary's College/Leinster), Geordan Murphy (Leicester), Ronan O'Gara (Cork Constitution/Munster), David Quinlan (Northampton), Peter Stringer (Shannon/Munster), Andrew Trimble (Ballymena/Ulster).
Not considered due to injury: Guy Easterby (Blackrock College/Leinster), Denis Hickie (St Mary's College/Leinster), Eric Miller (Terenure College/Leinster), Brian O'Driscoll (Blackrock College/Leinster), Paul O'Connell (Young Munster/Munster), Alan Quinlan (Shannon/Munster), Frankie Sheahan (Cork Constitution/Munster).
N.B. ** = Subject to passing a fitness test
2005 AUTUMN INTERNATIONAL FIXTURES:
Saturday, November 12: Ireland v New Zealand, Lansdowne Road, 2.30pm
Saturday, November 19: Ireland v Australia, Lansdowne Road, 2.30pm
Saturday, November 26: Ireland v Romania, Lansdowne Road, 12.30pm