The Scots produced one of the tournament's great upsets last weekend with a dramatic 20-16 victory over pre-tournament favourites France.

Head coach Frank Hadden has been warning his troops all week that such a famous victory will count for nothing if they cannot back it up with a first away win in eight championship attempts.

But while Scotland are trying to build a reputation, Sunday's game is crucial for a Wales side determined to preserve their status as one of the leading forces in world rugby.

Injuries and suspensions have undermined their RBS 6 Nations defence and a heavy defeat to England last week shredded any dreams of back-to-back Grand Slams.

Williams described the contest as "massive as far as Wales are concerned'' - massive in the context of the 2006 RBS 6 Nations, and massive in terms of proving Wales are not one-season wonders.

''We want to give a performance to show we are just as good as last year, if not better, and that the England result was a one-off,'' he said.

''It will show how mentally strong we are having lost last weekend - and I am confident we can beat them.

''Scotland deserve to be on a high. Beating France was a massive win for them, and we experienced that last season, but it is only one win.

''Scotland played well on the day but France can play a lot better - there are two ways you can look at it.''