England prop Alex Corbisiero has suffered another injury setback to put his Rugby World Cup hopes in jeopardy.
Corbisiero suffered a back injury during his time off the bench against France at Twickenham last weekend.
The British and Irish Lions forward hasn't trained this week and will not be involved this weekend in the re-match in Paris.
Multiple knee and shoulder injuries have kept Corbisiero off the field since he starred for the Lions in Australia in 2013.
England head coach Stuart Lancaster admitted on Tuesday that his unavailability for this weekend could have a substantial effect on Corbisiero's potential selection.
“We do still have the Ireland game but unfortunately for Alex the decision about this weekend has been taken out of my hands and that could have a bearing long term,” Lancaster told The Telegraph.
“Well, not long term, but next week, as he has to be able to train and that’s not for definite.
"I don’t think it is going to be two or three weeks but the clock is ticking and we need to see him train, if not at the end of this week then by next week, and he didn’t train today. I don’t know long sciatic pain takes to settle.
“All I can say on what I have seen in the camp, he has done all the work everyone has done so he has not missed sessions. Clearly some of the front rowers don’t do everything all of the time but he has been great.
"He is certainly pushing both Mako [Vunipola] and [Joe] Marler but we need to make sure we make the right decision because the fifth-choice prop, who can play tighthead and loosehead, has to be robust enough."