Ireland and Argentina appear to have the greatest chance of challenging the accepted world order but have been drawn in the same pool alongside hosts France and it would be a huge achievement for either side to reach the final.

The International Rugby Board have voiced their determination to increase the number of competitive sides in Test rugby and O’Sullivan insists they should focus their attention on the Pacific Islands.

Made up of players from Fiji, Samoa, Tonga, Niue and the Cook Islands, they have been crippled by the defection of star players to New Zealand and Australia.

But given more exposure, O’Sullivan believes Ireland’s opponents at Lansdowne Road on Sunday will become a force to be reckoned with.

“The Pacific Islanders have a huge role too play in world rugby. One of the problems with the game is that the World Cup is dominated by a handful of sides,” he said.

“If the World Cup is to develop as an entity it has to be competitive, exciting and unpredictable. Who wants to go to a World Cup where you know the semi-finalists before you’ve even bought your ticket?

“People can talk about the likes of sleeping giants America and the progression of Argentina, but there is a hotbed of rugby in the Pacific Islands. Unfortunately it hasn’t blossomed in the professional era.

“It was in a much healthier state in the amateur days but since the game went professional, there has been a haemorrhaging of their better players into the Australia and New Zealand teams.

“A lot of these players who would be eligible to play for their countries of birth end up playing for New Zealand or Australia and that has weakened them dramatically.

“It’s very hard to stop that and there’s no reason to stop that. We’ve picked New Zealand-born Isaac Boss last weekend so we’re not going to be critical about it.

“But that’s the dynamics of the situation. If the Pacific Islanders were able to pick their best team it would up the ante considerably for everybody.

“One of the ways to solve the World Cup problem in the game is to make the Pacific Islands stronger. Their current tour is an attempt to give them more exposure.

“There’s talk of them becoming a Tri-Nations team. The IRB are trying to help them and it’s a worthwhile challenge for them.”

The Pacific Islands lost their previous two games on tour against Wales and Scotland but finished strongly in both matches and O’Sullivan knows they can be lethal in broken play.

“It’s a classic Pacific Islands outfit. They’re very physical and they like playing with the ball in their hands,” he said.

“Scotland got off to a flyer against them last weekend and relaxed little bit, and suddenly they were nearly reeled in. These guys can create tries out of nothing – a soft shoulder here, half an offload there.

“They’re hard to chase down and are great finishers. Their strike-rate is excellent. They have capacity to hurt you out of nothing.

“They were put together a couple of years ago and are trying to mix different players from different countries. It’s like pooling Ireland, Scotland and Wales together on tour.

“They feel they will get better with every game and will be a more cohesive unit this week.”