The Cardiff flanker, voted Six Nations player of the tournament after his country's championship-winning triumph over Ireland, rejected suggestions that playing for the Blues' in the Celtic League clash at Hughenden will be a massive letdown just six days after the Millennium Stadium success.
Cardiff must beat Glasgow to have any chance of earning a place in next season's Heineken Cup and Williams said in today's Daily Record: "It won't be a case of basking in any glory. It is back to real work in a big way.
"At the end of the day, this is what we are paid for and we must remain switched on. If the international guys don't keep up their level of performance then they won't keep their place in the Wales team. The Glasgow match is huge for the club."