OSullivan made eight changes for the 55-6 victory over the United States in order to give his fringe players a run-out but has fielded his strongest available line-up for the Pumas clash.

Wasps flanker Jonny OConnor returns at openside to win his second cap, keeping Denis Leamy - who impressed against the Eagles - out of the squad, although his inclusion is subject to a fitness test.

OSullivan said: OConnor has a knee injury. He picked up a knock in training but his recovery has been good and we expect him to be fit for Saturday. We will make the final decision on Thursday.

OConnor enjoyed a fine Test debut against South Africa and his loss would be keenly felt by the Triple Crown winners, who will hand either Eric Miller or Leamy the number seven shirt if he fails to recover.

Five of the three-quarter line are supplied by Leinster with the midfield partnership of Brian ODriscoll and Shane Horgan linking up once again following their heroics against the Tri-Nations champions.

Munsters Ronan OGara and Peter Stringer take the half-back duties - they were on the bench last Saturday - while Leicester star Geordan Murphy is switched from full-back to right wing.

Three other members of the squad are carrying slight knocks but OSullivan is confident they will be given the all-clear to face an Argentina side full of confidence after their 24-14 victory over France.

He said: Guy Easterby took a knock on the knee against the USA but is back now. David Humphreys has a groin strain but has been in good form during training.

Stringer had a tight back which only surfaced on Sunday but that has already cleared up.

Ireland team to face Argentina at Lansdowne Road on Saturday:

G Dempsey (Leinster); G Murphy (Leicester), B ODriscoll (Leinster, capt), S Horgan (Leinster), D Hickie (Leinster); R OGara (Munster), P Stringer (Munster); R Corrigan (Leinster), S Byrne (Leinster), J Hayes (Munster), M OKelly (Leinster), P OConnell (Munster), S Easterby (Llanelli), J OConnor (Wasps), A Foley (Munster).

Replacements: F Sheahan (Munster), M Horan (Munster), D OCallaghan (Munster), E Miller (Leinster), G Easterby (Leinster), D Humphreys (Ulster), K Maggs (Ulster).