Jones aggravated the injury in training and will be out of action for around three weeks, which leaves him a major doubt for the Llanelli Scarlets Heineken Cup quarter-final against Munster on March 30.

Wales head coach Gareth Jenkins reacted to the unexpected news by promoting Thomas from the bench to lead the team from inside centre with James Hook shifting to fly-half.

It will only be Thomas third start for Wales in 13 months due to a combination of injury - he suffered a mini-stroke during last years 6 Nations - and suspension.

And he has been plunged in at the deep end. Wales head into the England game on a run of five straight defeats, facing the prospect of the wooden spoon and a Six Nations whitewash.

Thomas lost the full-time captaincy to Jones before the 2006 autumn international series and his only rugby in the last eight weeks was off the bench in Wales defeat to Italy.

But it took him no time at all to rise to the challenge - and Thomas expects Wales to do the same against the old enemy on Saturday.

Gareth asked me if I wanted the captaincy under these circumstances. Whether we had won or lost the last 10 games, I would never turn down the chance to captain my country, said Thomas, who will win a Welsh record-equalling 92nd cap at the weekend.

Its a big disruption with Stephen going because he is a good leader and the guys like him being around so he is going to be missed.

But its important we fill the gap and motivate ourselves to put in a good performance.
Ive been thrown into circumstances that arent brilliant.

Ill go out there on Saturday, lead my country against England, whatever criticism is flying around, and Ill be upbeat and motivate the boys as well as I can.

Thomas vowed to dedicate any triumph over England to Jones, who has been under immense pressure as Wales struggled through the Championship.

Thomas said: Not only is Stephen my team mate but he is one of my best mates so I really do feel sorry for him.

Stephen has taken a lot of stick and it would be good to dedicate a win towards him.