Mike Ruddock's side bounced back from last weekend's 50-44 defeat in Tucuman to run out 35-20 winners in Buenos Aries.

Williams claimed a first-half try hat-trick to prove Wales had the killer instinct to go with their new found forward power.

And the Neath-Swansea Osprey's star was quick to praise the service of those at his side.

The forwards fronted up, particularly the front row, and I had a great service from that platform and the backs inside me, said Williams.

Wales coach Mike Ruddock was delighted to claim the victory and equally pleased Williams had pin-pointed the team effort for his moment of glory.

Ruddock said: Shane was right to acknowledge the efforts of the forwards. We had put individuals and the squad under pressure during the week and the real difference between the first Test and the second was our attitude.

We showed mental toughness to go out there and put our game plan fully into place and in the second half when Argentina fought back we again pulled ourselves back from the brink and ensured they couldn't overhaul us.

Wales travel to South Africa now to face the Springboks in Pretoria on Saturday with Ruddock concerned at the effect such a schedule will have.

We don't want to make our excuses before we start and we want to test ourselves against the best, said Ruddock.

But it is going to be difficult with an overnight flight and then to go straight into preparation for a game that will be played at altitude.

Wales will make the journey with a clean bill of health which is remarkable considering the physical nature of their games in Argentina.