Conor Murray has prepared himself to play a role in all of Ireland's World Cup matches, with just two specialist scrum-halves in Joe Schmidt's squad.

British and Irish Lions number nine Murray may take a seat on the bench for Sunday's Wembley clash with Romania, with Eoin Reddan likely to step up to keep both men fresh.

Fly-half Ian Madigan is head coach Schmidt's emergency scrum-half, but Murray is happy to keep ploughing away to alleviate any undue pressures on the Ireland squad.

Kiwi boss Schmidt will look to mix up selection for Ireland's second Pool D encounter, with one eye on the pivotal battles with Italy and France.

"Mentally you have to prepare to be involved in every game," said Murray.

"And all going well you should be involved in most games, if not all of them.

"So it doesn't change for me or Eoin during the week, we're both preparing for a Test match at the weekend.

"If there were three or four scrum-halves in here they would be doing the same thing, because anyone can be called to slot in at any point.

"And you have to slot in without disrupting the team."

Leinster stalwart Reddan was icing his knee after Saturday's 50-7 victory over Canada but has trained without issue through the week.

The 34-year-old is the obvious candidate to step up and start against Romania in London, easing the burden on Munster playmaker Murray.

Madigan could well start at 10 or 12 to keep Johnny Sexton fresh, and that would compel both recognised scrum-halves into action once again.

Schmidt tasked Madigan with learning the details of scrum-half play as long ago as last summer, mindful of the need to squeeze as many varied resources as possible into his final 31-man World Cup squad.

Leinster and Ireland's skills coach Richie Murphy went to work with Madigan behind the scenes on recalibrating several elements of his directional play, leaving Schmidt happy to eschew a third specialist scrum-half.

Murray and Reddan have offered Madigan a guiding hand throughout, but the Munster pivot said Leinster's utility playmaker hardly needs his hand held.

"During the World Cup camps over in Ireland and over here, he's been doing his bit of passing and box-kicking and just chatting around the hotel to me and Eoin about things," said Murray.

"He's got a good idea of how the game of rugby is played and what he expects his nine to do, so that's something that will come quite easily to Ian I think.

"He's been there a few times with Leinster when they've had sin-bins or injuries or things, so he's not a complete stranger to it and I'm sure he's had a dabble in it as a youngster too.

"Ian's a very talented, skilful player, he can play full-back and centre comfortably so nine is just another string he can add to his bow.

"I've had a lot of conversations with Ian over the pre-season and the last few weeks.

"It's his own game really, you can't tell a fella how to play.

"Maybe if he needs a pointer here or there in terms of decision-making at nine that he probably would just take for granted when he's playing at 10 or something like that.

"But it's just little chats here or there it's not one or two specific things, it's just constantly talking to each other just in case.

"He's a natural playmaker and we back him to back his instincts.

"I won't tell Ian how to play, if he needs something from me in terms of nine he's not afraid to ask questions.

"I've known him for years, he's a good friend of mine and it's a natural process."