Despite missing out on the Six Nations by the slimmest of margins, the Irish showed they are a team at the peak of their powers with a good mixture of youth and experience. Their back line boasts huge experience from scrum-half to centre, and their pack contains a number of players whose experience belies their youth.

1. Ronan O'Gara. Everyone knows how good O'Gara is on attack, leading this year's Six Nations in points and tries. There is little doubt he will once again be the leading Irish points scorer and direct their fearsome back line, but it will be how well he defends that will determine Irish fortunes. When the Lions toured New Zealand in 2005, O'Gara was regularly shown to be a defensive liability, and rival teams will be sending their big men like Sebastian Chabal or Jerry Collins directly at him. Ireland will need O'Gara to make every one of those tackles, or shift Gordon D'Arcy in closer to help out if they are to challenge the Springboks or All Blacks.

2. Back line. Continuing on from the play of O'Gara will be the play of the backs around him. Brian O'Driscoll and D'Arcy are quite possibly the best centre pairing that will be on show at the World Cup, and these three men will receive excellent service from 72-Test veteran Peter Stringer at scrum-half. Geordan Murphy also provides a threat with his attacking runs from fullback, injecting himself into the line with superb timing and explosive pace.

'Brian O'Driscoll and Gordon D'Arcy are quite possibly the best centre pairing that will be on show at the World Cup'

3. Experience. Ireland may have the most experienced squad across the board at this World Cup. England showed in 2003 that experience plays a vital role in winning a World Cup, and Ireland have buckets of it. Six of their players have played in excess of 50 Test matches and four over 70. With so much experience in the squad, the Irish know how to keep their cool in the white-hot cauldron of international rugby, which should keep them from making silly mental errors that could cost them the tournament.

4. Fitness. This squad has a lot going for it, but their biggest weakness has been their tendency to drop their intensity during games. Against Scotland in the Six Nations, the Irish could not put away their opponents despite having a number of chances and needed two late O'Gara penalties to win the game. Once the World Cup gets down to the knock-out stage, being able to put away your opponents becomes critical, and if Ireland let teams like France, South Africa or New Zealand back into games, it could well be their undoing.

The Irish have a tough draw with hosts France and Argentina in the same pool, but topping the group will see them face a much easier semi-final. However, topping the pool means their road to the World Cup goes through South Africa, finishing runners-up puts the road through New Zealand - but nobody said winning the World Cup was easy. If the Irish pack can gain parity with the Southern Hemisphere packs, they have the back line to beat any team if they put them away when they have the chance.