The ERC has suspended Gareth Thomas for four weeks with immediate effect just hours after the player was provisionally selected in Wales's team for their opening Six Nations game against Ireland in Cardiff on Sunday.
Thomas attended a disciplinary hearing in Dublin this morning to answer charges of "misconduct" and "aggressive" behaviour towards Ulster spectators during Toulouse's Heineken Cup win on January 21st. He was found guilty of misconduct and not guilty of "aggressive exchanges with supporters".
In a statement the ERC said it had: "imposed a sanction of four weeks suspension on Mr Thomas from February 1st, 2007, up to and including February, 28th, 2007, and a fine of €7,500. The player will be available to play again on March 1st, 2007."
Thomas's absence is another body blow for Wales coach Gareth Jenkins who is already without a number of first team players, namely wingers Shane Williams and Mark Jones.
Harlequins' Hal Luscombe moves from centre to replace Thomas on the right wing, while Jamie Robinson of Cardiff comes in at outside centre alongside new Welsh hope James Hook. Hook and rookie winger Chris Czekaj are the Six Nations debutantes in the backline.
The experienced Kevin Morgan starts at fullback. Robinson is replaced on the bench by uncapped Newport Gwent Dragons youngster Aled Brew.
"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 of the suspension.
"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."
In the pack, blindside flanker Alix Popham starts, allowing Ospreys' Alan Wyn move to second row instead of the injured Ian Evans.
Tighthead prop Adam Jones is dropped from the squad and replaced by Worcester's Chris Horsman, who will work alongside hooker Rhys Thomas and Gethin Jenkins in the frontrow.
Jenkins reassured those omitted players that there will be every chance to reclaim their place.
The absence of Gavin Henson raises eyebrows given the fact the coach specifically requested he play at fullback for the Ospreys last weekend. But the Ospreys player was poor against Ulster and Jenkins was ruthless in his decision.
"Gavin was left out purely on form, he didn't warrant his place," said Jenkins.
Wales: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).
