Even without star tighthead Andrea Lo Cicero, who has been named on the bench after recently recovering from a knee injury, the Azzurri are a formidable outfit up front.
They will be desperate to blunt Ireland's attacking ambition by drawing them into a battle in the tight - a situation O'Sullivan is keen to avoid.
"We'll have to move the ball away from Italy's pack as much as possible," he said.
"Two years ago we played them at Lansdowne Road in what was a wind tunnel. We couldn't pass the football and had to take them on at their own game. It was a really physical encounter which didn't suit us at all.
"We won but it's important we don't try to take them on at their strengths, which is in their forwards. If we have to take them on up front we will - we've done that before and won.
"But it's a harder day's work because they take a lot of breaking down."
He continued: "We've seen Italy progress as a team. They've developed dramatically from a defensive point of view.
"They defended poorly against Australia last summer but have tightened up significantly since then.
"They play a much more aggressive defence and will use that approach against us."
Carlos Nieto makes his first RBS 6 Nations start in place of Lo Cicero while Christian Stoica has been switched from centre to full-back to accommodate for injuries to Andrea Masi and Denis Dallan.
Despite the changes O'Sullivan expects Italy will opt for traditional route one rugby with their pack winning ball for Stoica who will then try to smash his way through the midfield.
"A couple of the selections were unexpected - they've juggled their front row a bit with Nieto coming in which is a surprise," added O'Sullivan.
"But I don't think it's going to change their gameplan too dramatically," he added.
"They'll be playing to their strengths. They may use Stoica as a target runner - he's a huge ball carrier for them and will be running from deep at full-back, allowing him to generate even more speed than usual."
Ramiro Pez has returned to favour under new coach Pierre Berbizier for his first Six Nations start since 2003 and O'Sullivan has warned his side the Perpignan fly-half must be shackled.
"Pez is like most players in key positions. If his confidence is up he can be dangerous - and his confidence is up at the moment," he said.
"He has produced some fairly solid performances for Italy and is a key guy in terms of his running and kicking game. I expect him to run the game pretty well.
"He's an experienced guy now who has played in the Six Nations a few times. He's in a good run of form."
If the conditions remain good and they avoid getting bogged down up front, Ireland should enjoy a comfortable start to the championship.
Their backline should have the edge through centres Brian O'Driscoll and Gordon D'Arcy close to top form while there is plenty of threat offered out wide through Shane Horgan and Tommy Bowe.
An impressive victory is essential if Ireland are to build momentum ahead of next Saturday's daunting trip to Paris where favourites France will be out to deliver a reality check to Irish ambition.