Gareth Thomas has been ruled out of Wales' game with Ireland after receiving a four-week ban.
Thomas will miss at least three Six Nations games
With wings Shane Williams and Mark Jones out injured, Chris Czekaj and Hal Luscombe form an inexperienced flank partnership, Jamie Robinson at centre.
Wales have chosen a powerful pack, props Gethin Jenkins and Chris Horsman picked ahead of Duncan and Adam Jones.
Locks Ian Gough and Alun Wyn Jones have behind them a back row of Alix Popham, Martyn Williams and Ryan Jones.
Coach Gareth Jenkins is thought to have turned to a muscular pack having seen Leicester overwhelm Munster in the Heineken Cup, six forwards from the Irish province being selected in the Ireland eight.
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Thomas received his suspension from a European Rugby Cup panel in Dublin for engaging in "aggressive entry of the seating areas" and "making offensive hand gestures" after an incident in a match between his side Toulouse and Ulster.
We always had a contingency in place which is robust and we'll now deal with the Irish challenge on that basis
Wales coach Gareth Jenkins
That means that the ex-Wales and Lions captain - taking part in his final Six Nations - will not be available until 1 March and misses games with Ireland, Scotland and France.
Wales could yet appeal against the ban, although ERC say that they could have excluded the utility back for up to 12 weeks.
"We are obviously all hugely disappointed, but we always had a contingency in place which is robust and we'll now deal with the Irish challenge on that basis," said Jenkins.
"Our main focus has to be the match on Sunday and preparing the squad of players we have selected to perform in front of a sell-out Millennium Stadium crowd."
Welsh Rugby Union group chief executive Roger Lewis added: "Together with our lawyers, we will be carefully considering the implications of this ruling."
Luscombe missed the autumn Tests due to injury
Luscombe was originally due to partner James Hook in the centre, but his move to the wing leaves a potentially fragile pairing of Hook and Robinson to face Brian O'Driscoll and Gordon D'Arcy.
Wales' team selection for Sunday's game at Cardiff's Millennium Stadium was delayed because of Thomas' case, and due to fruitless hopes that wings Jones (ankle) and Williams (hip) would be fit for selection.
Wales have also lost Bath number eight Gareth Delve to an ankle injury, Ospreys back-row Jonathan Thomas called up as squad cover.
Wales team to face Ireland: K Morgan (Dragons); H Luscombe (Harlequins), J Robinson (Blues), J Hook (Ospreys), C Czekaj (Blues); S Jones (Scarlets, capt), D Peel (Scarlets); G Jenkins (Blues), R Thomas (Blues), C Horsman (Worcester), I Gough (Dragons), A Wyn Jones (Ospreys), A Popham (Scarlets), M Williams (Blues), R Jones (Ospreys).
Replacements: M Rees (Scarlets), Duncan Jones (Ospreys), R Sidoli (Blues), Gavin Thomas (Scarlets), M Phillips (Blues), C Sweeney (Dragons), A Brew (Dragons).