Fabien Galthié, who gave France's bid for their third grand slam in five years a boost when he returned from injury against England last month, may miss the final match of the campaign against Ireland in Paris on Saturday because of a hamstring strain.

The 33-year old scrum-half will have a fitness test tomorrow and it is hard to overstate his importance to the side. Laboured victories without him against Italy and Wales were followed by emphatic displays against England and Scotland after his return.

The injury forced Galthié to pull out of training yesterday but the wing David Bory, the flanker Serge Betsen and the No8 Imanol Harinordoquy were all passed fit to play.

The closest France have come to defeat this year was at the Millennium Stadium where Wales were denied two stoppage-time scores by the video referee, the first of which was claimed by Scott Quinnell who misses Saturday's Cardiff encounter with Scotland because of a knee injury. He has been replaced as a No8 and as captain by Colin Charvis.

Charvis was dropped from the Wales squad two months ago after flying out for a holiday to Jamaica rather than take part in training sessions and he admitted that he was more than mildly surprised when the caretaker coach Steve Hansen asked him to take over the captaincy at breakfast last Monday, April Fool's Day.

"I was just delighted to get back into the side," said Charvis, who has only played No8 for Wales once before. "It was a shock to be asked to lead the side and I had no hesitation in accepting. When Steve took over from Graham Henry in February, he spoke to the A squad, which I was then in, and told everyone that the slate was wiped clean and that he would be judging everyone on performance. He has been true to his word."

Hansen has made five changes from the side which suffered a record defeat to England at Twickenham last month and there is a clear shift in emphasis after an afternoon when Wales were left gasping for air because of the pace at which the game was played.

"A problem with the club game in Wales is that the ball-in-play time is too low," said Hansen. "Players and coaches at club level have to get to grips with that fact as do referees. The top countries in the world, like England and Australia, play at a pace which we cannot yet match."

Scotland, who will name their side today, will be at full strength after the second row Scott Murray and the centre John Leslie were yesterday passed fit.

Wales: K Morgan (Swansea), R Williams (Cardiff), Taylor (Swansea), Marinos (Newport), C Morgan (Cardiff); Jones (Llanelli) or Harris , Howley (both Cardiff); Thomas (Ebbw Vale), B Williams (Neath), Anthony , I Gough (both Newport), A Moore (Swansea), Budgett (Bridgend), M Williams (Cardiff), Charvis (Swansea, capt). Replacements: R McBryde (Llanelli), S John (Cardiff), C Wyatt (Llanelli), G Thomas (Bath), D Peel (Llanelli), Harris or Jones , D James (Bridgend).

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