"We are terribly disappointed for Ceri, who is such a great player and popular member of the squad," said Wales Coach Mike Ruddock. "However, it's comforting to know that we have a replacement of the quality of Nicky (Robinson).
"We will know more about Ceri's injury on Monday, but the hope is that he will be back in contention next week. Nicky is an established member of the squad and as such his transition into the match-day 22 should be a smooth one.
"He was instrumental in our win over Argentina on my first tour as Wales coach in 2004 and he also figured on our North American tour and the recent Autumn internationals so he is no stranger to our style of play."
Sweeney pulled up in training this afternoon and was ruled out of contention for this weekend's clash by the Welsh medical team. Robinson has trained with the squad for the last week and today passed a fitness test on the injured shoulder that kept him out of the Blues' recent Heineken Cup campaign.