The Irish, world-ranked sixth and with an enviable tournament record of 18 wins in 25 starts, go into the 2005 running as arguably the favourites to lift the 200-ounce sterling silver trophy in March. Nevertheless, O'Sullivan is wont to even dismiss the Italian challenge, adopting the age-old mantra of 'one game at a time.'
"There's a lot of talk about this Irish side having a great opportunity and I wouldn't disagree with that," said the Youghal-born coach.
"But I think the one thing we have to do as a team and as a squad is not get ahead of ourselves. There are five games. It's cliched and boring but the facts are you've got to jump the fence in front of you, and not the fence two jumps away.
''The most important thing is to get to Rome on Sunday and dig out a result. It won't be an easy result. We know the Italians will start fresh and having seen them beat Scotland and Wales before, we don't want to be their next victims,'' he added.
Entering his fourth Six Nations as the second-most experienced coach in the tournament behind France's Bernard Laporte, O'Sullivan has been impressed by recent viewings of John Kirwan's Italy.
"I think they've changed their game a little bit. In fairness to John Kirwan, whose a good friend of mine, he's worked very hard at putting extra dimension into their game.
"Their defensive system has got tighter. And I thought they had a pretty good autumn.
"We've just got to focus on the job in hand and that job is Italy,'' he stated. "They're going to have the ball for long periods because they have a good set-piece and their continuity is good - so they're not going to give the ball away.
If famed-insomniac O'Sullivan is restless at night dwelling on the Azzurri's set piece, then it's safe to say that the new IRB tightening of the breakdown laws is also keeping him awake.
The Ireland management received a DVD package from the International Board last Wednesday, like every other nation, illustrating the new interpretation of the tackle ruling (i.e. Referees have been asked to adopt a 'zero-tolerance' interpretation of the laws when a player is tackled - forbidding him to move his body to protect the ball) and O'Sullivan is wary of what might happen.
"This is going to be difficult on referees and difficult on players and has the propensity for the first couple of weeks until people get their heads around it to be an area of a lot of controversy,'' he commented.
"If you go to ground with the football, if you make any movement to protect the ball after you have made contact with the ground, it is a penalty.
"To be fair to the IRB, they feel the player in possession is often getting too much time to protect the ball and they are trying to make it a fair contest," added O'Sullivan.
"That's sounds simple but it is a collision sport and people fall in all sorts of directions, especially when you are being tackled by two people at the same time.
"I think the referees will have to be sensible. There could be a lot of penalties on Sunday."