At his daily media conference the Irish coach said: this is our fourth pool game in which we will have played against three Southern Hemisphere teams with Southern Hemisphere referees and there are big issues.
Unfortunately, last week, we came out on the wrong side of referee Andre Watson (South Africa) by 13 - 8 on the penalty count and in a game that tight it's a very scary place to be.
We had Paddy O'Brien (New Zealand), the referee against Australia on Saturday in the Six Nations in 2002 and again we got hammered 12 - 6 on penalties in Paris. I spoke to Paddy in Adelaide as he ran the line in our game against Argentina. He assured me he had no issues with our play. He said we did a good job.
I take the man on his word that there won't be any issues on Saturday. It is a concern in a tight game when you get an overload. You wonder what you are doing wrong. These calls make all the difference. I'd be telling a lie if I said I was not worried about that aspect of the game.
In naming his strongest team possible - Victor Costello (thigh injury) is the only one of the 30 man squad not considered, We said we would put our best foot forward in every game and that is what we have done. If we did anything less than pick our best team we would be capitulating to a game we believe we can win and we feel we have every right to go after.
I know we won't be favourites. That's no reason not to try and go and win it. Let the dice roll. I don't think you should leave anything in your locker in the World Cup. You should put your best foot forward every time and that is what we have done.O'Sullivan believes the return to the side of Irish born Keith Gleeson, who learned his rugby in Australia can be a plus factor for Ireland. Said the coach: Keith is a very good open side flanker. He also knows some of the Aussie boys. He played with them on the way up. I think he will want to prove a point, which is always a good way to go into a game.