Ireland kicked off their campaign with victory over Italy but it was a poor performance which has shattered the air of optimism shrouding the national side.
A daunting trip to Paris is their next championship appointment and they must produce a significant improvement if they are to escape a heavy defeat on Saturday.
But while skipper O'Driscoll warns more of the same will lead to ruin in the French capital, he insists Italy's commitment ensured the match was always going to be a war of attrition.
"If we go out and play like that against France we'll be in serious trouble," he said.
"Italy are a hard side who played well. We didn't play well but managed to grind out a win. There will always be games like that.
"Six Nations rugby is always difficult, whether you're playing France, Italy or England.
"I'm an eternal optimist and I'll try to take the positives out of this result."
Italy's aggressive defence, especially in midfield where Mirco Bergamasco and Gonzalo Canale caused havoc with a raft big hits, clearly rattled the Irish.
The Italians closed down the space so effectively that Ronan O'Gara's crossfield kicks to the wing were the only successful avenue of attack.
O'Sullivan has demanded more penetration against France and the Ireland coach suspects that will come against a side which likes to put as much width on the ball as possible.
"France will a different game. If we don't get over the gainline we'll be in trouble," he said.
"Having said that France will throw the ball around and it will be a more open game. That will suit us. Italy controlled the pace of the game, slowing it down.
"Next week won't be so stop start, it will be a lot livelier. We'll have to set out our stall and get a platform to run off. We must get over the gainline if we are to generate momentum."
The first half finished 10-10 with Mirco Bergamasco and Jerry Flannery crossing and if Italy can prove Saturday's effort was not a one-off, they have a great chance to avoiding the wooden spoon.
"Pace made a big difference to us. We lost the ball sometimes and conceded too many passes but we were competitive for 80 minutes and could have won the game," said coach Pierre Berbizier.
"I have to thank the players and especially Marco Bortolami because he had fever and a 40 degree temperature over the last few days but still played.
"Now we have to think about next week when we face England. They are very strong but we want to challenge them in the same way we challenged Ireland.
"We want to leave the Stadio Flaminio in the same manner we left Lansdowne Road - with our heads held high."
O'Driscoll, who along with centre partner Gordon D'Arcy was tackled out of the game, believes Italy are a team on the up.
"Italy have improved, particularly in their defence which was very impressive," he said.
"They closed down our options and we had to think latterly, hence Tommy's try. They are a team improving year by year. Their players want to impress the new coach and cement their place in the side."