|Rugby World Cup|
|Hosts: England Dates: 18 September-31 October|
|Coverage: Live on BBC Radio 5 live and sports extra, BBC local radio, plus live text commentary on every match on the BBC Sport website.|
|Further coverage: BBC Radio Wales, BBC Radio Cymru, BBC Radio Scotland, BBC Radio Ulster and BBC Local Radio.|
Ex-New Zealand scrum-half Justin Marshall doubts whether Ireland have the creativity to go all the way at the World Cup.
Marshall believes that Jared Payne is a "makeshift centre" and that Ireland's attack has been "lacklustre" at times.
"They do not have a (centre) combo that really do challenge," said the 81-times capped Marshall on BBC Radio 5 Live.
"When you have that, spaces open up for the outside backs and inside backs that completely change the game."
Marshall, who won 81 All Blacks caps between 1995 and 2005, believes that the Ireland backline has struggled to fill the gap left by Brian O'Driscoll's retirement even though the Irish managed to retain the Six Nations title earlier this year.
|Ireland's remaining World Cup Pool D games|
|Sunday, 27 Sept, 16:45 BST: Ireland v Romania, Wembley Stadium|
|Sunday, 4 Oct, 16:45 BST: Ireland v Italy, Olympic Stadium|
|Sunday, 11 Oct, 16:45 BST: Ireland v France, Millennium Stadium|
Payne was among the try-scorers as Ireland notched seven touchdowns in Saturday's opening 50-7 win over Canada but the Irish will face much tougher World Cup tests including the concluding Pool D game against France on 11 October.
"When you go into a restructure like they have when you lose quality centres (like O'Driscoll and Gordon D'Arcy), you are trying to forge a way forward," added Marshall.
"You've got to be slightly conservative with the way you go about implementing your game plan.
"For me, Jared Payne is a back-three player so he's a makeshift centre. And a lot of their lacklustre attack is because they have not got a (centre) combo that really do challenge."
Ireland attack one-dimensional - Tindall
Former England centre Mike Tindall also believes that Ireland may "struggle creatively" when they face the stronger nations later on in the tournament.
"I think they are a bit one-dimensional in attack," added 2003 World Cup winner Tindall.
"They have a very structured game. They are incredibly good at getting their aerial kicks back and (Johnny) Sexton is one of the best tactical kickers in the game at the moment and Schmidt is one of the best tactical coaches.
"But I don't know if they go up against someone like New Zealand whether they will have the ability to score tries.
"That is my only question with them. Everything else they have got.
"It will be interesting when they play the big game against France whether they can muscle up against the French pack and also be creative enough."
After their opening win over Canada, Ireland are back in action against Romania at Wembley on Sunday and they face Italy on 4 October before the concluding pool fixture with France.
|More from rugby:|
|Get World Cup alerts direct to your phone|
|Rugby World Cup 2015 fixtures and groups|
|Ferris encouraged by Ireland's start|
|Horan, Tindall and Marshall on the RWC podcast|
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