Ireland welcome back five Lions to their starting XV for the second of their back-to-back clashes with the French, while Wales recall the same number for their final friendly fixture of the summer.
Former Lions skipper Brian O'Driscoll has recovered from a neck cum shoulder injury and is joined in the Irish midfield by Gordon D'Arcy who has battled back to fitness following ankle surgery.
Jamie Heaslip starts at No8 and 2009 Lions leader Paul O'Connell is named at lock after the pair were on the bench in Bordeaux last week, while fellow Lion David Wallace comes into the team on the openside flank.
Neither Rob Kearney or Tommy Bowe are named as they look to fully recover from minor knocks but Stephen Ferris is included in the matchday 22 for the first time since November 2010.
Ferris, who saw his first Lions tour brought to a premature end due to injury, hasn't played since damaging his knee back in January.
Elsewhere in the Irish side, Munster's Felix Jones makes his first start in the No 15 shirt, with Jonathan Sexton and Tomas O'Leary named at half-back. Keith Earls moves to the wing to accommodate D'Arcy and O'Driscoll, with Sean O'Brien switching to blindside following the inclusion of Wallace.
Ireland coach Declan Kidney has also named his team for a lesser encounter with Connacht on Thursday evening - a game which will allow him to take a closer look at a number of fringe players before he names his 30-man World Cup squad on Monday.
Geordan Murphy, a Test Lion in 2005, will be looking to show that he is now fully recovered from a serious ankle injury that saw him sidelined for the final four-and-a-half months of the season, while Shane Jennings will be making his first appearance since overcoming a broken arm.
Meanwhile, Wales are able to name Adam Jones, Lee Byrne and Leigh Halfpenny in their starting side after the trio proved their fitness in training this week.
The 2009 Lions had been struggling with toe, knee and ankle injuries respectively and hadn't featured for their country since the last RBS 6 Nations match against France in March.
Warren Gatland has also recalled Ryan Jones and triple Lions tourist Martyn Williams to the starting XV to take on the Pumas at the Millennium Stadium, with Jones set to equal Ieuan Evans' record of 28 Tests as Wales captain.
Stephen Jones has recovered from a calf strain but has to settle for a place on the bench as James Hook is preferred at outside-half.
Tavis Knoyle starts at scrum-half, with fellow Scarlet Jonathan Davies named at outside centre and Jamie Roberts switching to the inside berth in the absence of the injured Gavin Henson as Gatland makes nine changes to his starting side.
Ireland (vs France, Saturday, 5pm)
F Jones, A Trimble, B O'Driscoll, G D'Arcy, K Earls, J Sexton, T O'Leary; C Healy, R Best, M Ross, D O'Callaghan, P O'Connell, S O'Brien, D Wallace, J Heaslip
Replacements: J Flannery, T Court, M McCarthy, S Ferris, E Reddan, R O'Gara, L Fitzgerald
Ireland Select XV (vs Connacht, Thursday, 6.30pm)
G Murphy, J Murphy, D Cave, I Keatley, F McFadden, P Wallace, I Boss; T Buckley, S Cronin, J Hayes M O'Driscoll, L Cullen, K McLaughlin, S Jennings, D Leamy
Replacements: D Varley, M Horan, D Ryan, N Ronan, C Murray, D Hurley, I Whitten
Wales (vs Argentina, Saturday, 2.30pm)
L Byrne, L Halfpenny, J Davies, J Roberts, G North, J Hook, T Knoyle; P James, R Hibbard, A Jones, B Davies, A-W Jones, D Lydiate, M Williams, R Jones
Replacements: H Bennett, R Bevington, A Powell, J Tipuric, L Williams, S Jones, A Brew