Argentina captain Agustin Pichot claims Ireland are not the team they have looked in their three disappointing World Cup matches so far.

Pichot disagrees with the assessment that Ireland, who must win scoring four tries and by more than seven points to survive in the tournament, have played poorly so far and points to the psychological pressure faced by Eddie O'Sullivan's side as a possible reason for their slump in form.

"They are one of the five best teams in the world. For us Ireland are not the team of the first three matches, for us Ireland is Ireland," Pichot said ahead of the Pumas' final Pool D clash on Sunday.

"The expectations are always big for Ireland. They are expected to walk into the World Cup and qualify," he said. "Rugby is a very simple game still, it's psychological and this World Cup is proving that.

"Ireland played very well against France," he added despite the fact that the French won that match 25-3 last Friday. "They were not consistent against Namibia and Georgia."

Argentina top the pool after upsetting France 17-12 then beating Georgia 33-3 and Namibia 63-3. They are the only team not to have conceded a try in the tournament.

He said the situation for Sunday's match, Argentina's third World Cup clash with Ireland was "strange when you have to score four tries".

He said the encounters were three very different scenarios. Argentina eliminated Ireland 28-24 in a last-eight play-off in 1999 then lost 16-15 in a pool meeting in 2003.

"In 1999, everything was new for us and we went into the match to see what would happen," he said. "In 2003, it was win or lose, there was enormous pressure and we weren't so settled as a team, not so confident."

This time, he says, his side are much better prepared for the encounter.