Everyone focuses on their pack - but this is an Argentinean team with a lot of strings to its bow O'Sullivan says.
From broken play they have scored quite a few tries from deep positions with counter attack. They have scored about six tries from 80 metres out. They are probably the most devastating in the tournament and I don't mind if the New Zealanders are upset by that.
Of the pressures facing the team for Sunday's crunch game, the Irish coach says: It's a no brainier. We want to win because that would put us into the quarter finals and that is our stated goal from the outset.
Everyone in the squad is aware. The ante's up and the chips are down so it's a big week. Yes, there is a bit more tension, but that's fine by me.
If O'Sullivan praises Argentina for their back division potential, he takes them to task about their constant moaning of a draw they perceive to be rough on them.
Belly-aching about a schedule in the week of a game does not make a lot of sense. The schedule was drawn up nine months ago. If anyone has problems they should have put up their hand then. It's a bit of bluster. They know well it's not going to change. Maybe they are trying to draw a bit of sympathy. I don't like the idea of playing Australia six days after meeting Argentina. But I'll get on with it. he says.
The omens are also promising for number 8 Anthony Foley. The knee injury that kept him out of consideration for Sunday's game has also responded well to treatment and he hopes to resume full training on Monday.