Williams, who scored three tries during Wales RBS Six Nations Grand Slam triumph, has been handed first opportunity by Sir Clive Woodward to press his claims for a starting berth on the tour of New Zealand against the Pumas in Cardiff.

''The more nervous I am, the better I play so hopefully that will help me in the game, he said.

Even though I am nervous I am excited as hell playing with the likes of Jonny Wilkinson.

''The intensity is starting to rise. It is the start of the tour now and Argentina are certainly capable of scalping teams but if we can come off that field with a good performance, a good win, it puts us in good stead for the tour.''

Williams knows competition is fierce to line up opposite the likes of Joe Rokocoko and Doug Howlett, with Josh Lewsey, Jason Robinson, Mark Cueto and Geordan Murphy among the leading contenders for the Lions.

However, Williams may be small, but he harbours giant ambitions.

''New Zealand have a back line capable of beating anyone and as far as I am concerned some of them are the best in the world - but I want to go out and compete against these players,'' he said.

''What better way to test yourself against arguably the best back three in the world? What better way to play rugby?

Williams' remarkable ascent to become one of the most natural, electrifying talents in rugby can be traced back to the latter stages of what had been a tough 2003 World Cup for Wales.

He was thrust into the side to play New Zealand as then-coach Steve Hansen gave his fringe players a rare start. Williams knew it was his chance.

He scared the life out of the All Blacks in Sydney and has developed under Mike Ruddock into a key figure in Wales' Grand Slam-winning side.

After the year he has had, it is easy to see why Williams feels nothing is impossible.

''That was a big game as far as I was concerned. It was make or break for me, he added.

I knew I would be competing against one of the best wings in the world and I knew I had a point to prove. Since then I have gone in with the same attitude and things just started to steamroll,'' he said.

''I started to enjoy my rugby again and right now I am absolutely loving it. I don't want this season to end.''