The musical serenade cut through the Argentina press conference penetrating deep into the concrete bunker in the Parc des Princes. Heads turned quizzically while Argentina coach Marcelo Loffreda and his captain Agustin Pichot exchanged a small smile.

Outside blue and white clad Argentinian supporters surrounded the team bus, greeting each player's arrival with a new volley of song. Their delight was understandable, the realisation that their team had delivered on a pre-match promise and guaranteed them another week in Paris.

Before yesterday's contest, Argentinian players and management peddled a similar mantra: that Ireland were a good team but that the Pumas boasted the quality and confidence to prevail. The postscript was similarly low key.

Loffreda and Pichot's body language bespoke the vindication, not in a brash way, of a well executed game plan.

It encapsulates everything about Argentina as a group of players and management; strong bonds forged by friendship, pride and passion in the jersey and an unwavering belief to adjust to the demands posed by every opposition.

They analysed Ireland, worked out the best way to beat them and then accomplished it with ruthless precision. Their gambits may at times seem one-dimensional and lacking in finesse but their effectiveness is undeniable.

The Pumas don't mind winning ugly, content with only the occasional brush-stroke of artistry. They are a rugby union's artisans, who champion the simple virtues and elevate the basic tenets of the game: scrum, lineout, ruck, maul, punting.

They endured an uncomfortable opening 15 minutes, and were twice sliced open by Ronan O'Gara's beautifully weighted passes and Brian O'Driscoll's quality, but they struck rigidly to their game plan, ratcheted up the pressure and awaited Ireland's folly.

Loffreda admitted: "Of course we are very happy. We have had to play a very hard game (and) it was going to be very difficult. Ireland were going to play very strong, very well. We knew that, we were expecting that.

"We did okay, we did the tactics okay. They (the team) followed the strategy that we had constructed. You know we made some mistakes, we lost two tries and that is something that we have to work very hard not to let happen again."

It was a minor cavil on a night when his team had accomplished what few thought possible before the start of the tournament; steering an unbeaten passage through the pool of death.

He continued: "I think that this represents a very important step for Argentina. It's a well-deserved win for Argentina and the players. We have moved out of this death group, as it is known, with great authority.

"We played exactly how we expected to play and this has got to do with decision-making. As a result of Ireland's pressure we did make some mistakes. We lost a lot of balls and they exerted a great amount of pressure on us. We had more habitual errors, especially when they scored their tries. Ireland had a huge amount of opportunities but the game was mainly dominated by Argentina."

Pichot endorsed his coach's assessment on the manner in which they game unfolded: "It was a very tactical match. We knew what had to be done. The coaches had us well prepared. We knew Ireland were a dangerous team and could take away our stability and control. When a team (like Ireland) can control the game it can get out of hand.

"It is a great achievement to win four matches; it's what we wanted to achieve. It was the most important factor for the team to show what we are capable of and we don't need to look at changing things. We need to look at the future, be prepared to play for what we believe in.

"We may not be tactically the best team in the competition, we may not be the biggest team or the strongest physically, but we played a very special match today."

The impact that this victory and all Argentina have achieved to date in this tournament and in recent years should guarantee a healthy future for the sport. Loffreda admitted: "There is a huge fervour in Argentina, a great deal of support for the team and this needs to continue. The recognition here on an international level, where Argentina could come fourth or fifth in the World Cup (means) we are showing that this is not a transition, this is proof of our position."

No one would quibble with that assertion.