Williams produced a moment of sheer magic to help inspire Wales to a famous victory.

That score, after 15 minutes, was Williams' second but epitomised the way Wales wanted play.

The diminutive Neath-Swansea Osprey's star shimmied and shuffled his way through a bewildered Pumas defence for a memorable touchdown.

It was part of a dream start for Wales.

They pinned the Pumas into their own 22 from the kick-off and unlike in the previous weekend's 50-44 defeat at Tucuman, Wales this time provided the killer instinct to their solid performance up front.

Welsh possession was, as coach Mike Ruddock had hoped, far cleaner and quicker on this occasion and the promise of the backline was soon to deliver.

Fullback Gavin Henson kicked his first penalty after seven minutes, punishing Pumas' second row forward Ignacio Fernandez Lobbe for offside.

Four minutes later Argentina fumbled a lineout, allowing Wales to launch a sweeping attack which brought the game's first try.

Welsh locks Brent Cockbain and Gareth Llewellyn set the move in motion and skipper Colin Charvis drove into the heart of the home pack to help build the momentum.

And when the ball emerged outstanding centre Tom Shanklin and Sonny Parker combined before the latter set Williams free on an unimpeded dash to the line and Henson converted.

Four minutes later Williams added his second with that moment of sheer magic which Henson again converted.

The fullback then added a penalty and after 38 minutes Williams was again to profit from some superb Welsh approach play.

Number eight Michael Owen broke from the back of a scrum, found support from the hard working Charvis and then halfbacks Dwayne Peel and Nicky Robinson combined to send the livewire wing over.

The Pumas' problems had been exacerbated by losing wing Jose Maria Nunez Piossek after eight minutes, centre Jose Orango after 24 and star fly half Felipe Contepomi after 39.

To add to their woes the home side saw Lobbe sin-binned after 30 minutes as the referee Donal Courtney lost patience with their persistent offside.

Wales went into the second half 25-0 ahead but found themselves on the rack from the restart.

Skipper Charvis was sin-binned two minutes after the break for a professional foul and suddenly it was Wales' turn to be under pressure.

The Pumas were clearly stung by Wales' outstanding dominance and clinical finishing in the opening period and with Charvis out of the fray launches a ferocious series of attacks to give them hope.

Fullback Hernan Senillosa punished Charvis's indiscretion with a penalty and three minutes later replacement Federico Martin Aramburu claimed the Pumas' first try converted by Senillosa.

Argentina kept up the pressure and were awarded when prop Omar Hassan crashed over amid a heap of bodies.

But Wales' nerves were soon to settle as Henson kicked a penalty.

And in the 68th minute the visitors finished off their host's brave fightback with another outstanding score.

Hooker Mefin Davies launched the counter-attack and in turn Parker, Shanklin and Shane Williams took the tackles and timed their passes to perfection for fly-half Robinson to go over for his first Welsh try.

Henson converted and Argentina got the consolation of a try from wing Lucas Borges deep into extra-time.

That happened after Williams was sin-binned for a professional foul but that indiscretion will soon be forgotten with Williams, the star of the show, now with 18 Welsh tries to his name.