The Test rugby minnows gave Ireland a tough examination at Limerick last September, testing them out wide and forcing mistakes with their committed brand of rugby.

The focus of Pool A is naturally on the games between Ireland, Argentina and Australia, with only two able to qualify for the quarter-finals.

While O’Sullivan is looking to build through the pool stages until their final two crunch fixtures, he nevertheless vowed to play his best possible side against the Romanians.

“If you get your gameplan right you have a chance of beating them. They are a team that we know what it takes to get past them,” he said.

“We played them last year and it was a very difficult game because they are quite a physical team.

“They all play their professional rugby in France, so there is a French influence on the team. They have a very strong pack of forwards, strong-running backs and they are very good at offloading in the tackle.

“They are a side that is well put together.”

The Irish are particularly well drilled themselves, having moved into third place in the International Rugby Board’s world rankings with 15 wins from their last 17 Tests.

While those IRB rankings are debatable – “they rankle the media more than the teams involved“, was Keith Wood’s assessment – what is for certain is that O’Sullivan has assembled an exciting squad of players.

Wood described the World Cup squad as the best he has played alongside in his Ireland career, despite injuries cruelly ruling out full-back Georden Murphy plus inside-centres Rob Henderson and Jonathan Bell.

O’Sullivan added: “I’m very happy with the quality of players we have in the squad.

“I think we have built a little bit of depth into the squad in most positions, which has always been a bit of a problem in Irish rugby with the numbers we have to work with.”