One of the most decorated half-back partnerships in Test rugby is coming under pressure from increased competition.

Ireland's first-choice partnership of Conor Murray and Johnny Sexton may not start start together this weekend in Rome, though that would be more of a nod to strengthening the depth of the Irish squad in a World Cup year than a reaction to the form of the Lions duo.

It has, however, been a tricky start in different ways for the pair as Ireland look to move into the positive side of the win/loss record in this championship.

Munster scrum-half Murray has battled back from an early season injury - he had just 495 minutes of rugby under his belt when England rolled into town earlier this month - and has struggled to hit the sky-high standards we have become accustomed to.

Outside of him, the reigning World Player of the Year Sexton also failed to make an impression, admittedly on the back foot against Eddie Jones' side, with the late intercept encapsulating his afternoon in a moment. 

Also short of playing time this season, he departed well before the half-time whistle against Scotland after shipping a heavy knock.

Joey Carbery came on and, after a nervy start, served up a timely reminder that his development is continuing at a rapid pace since his departure from Leinster.

With changes expected against an Italian side languishing again at the bottom of the table, the question for Schmidt is this: does he give Murray and Sexton more game time, or is it the ideal opportunity for others to slot in?

"I suppose with all these games it's about trying to get the right mix on the pitch," skills and kicking coach Richie Murphy said today.

"Joey, obviously, played a lot in the Scottish game so it's about trying to balance that up with game time for the likes of Johnny. So we've watched them training over the last few days, both guys are in good form, so we'll just make a decision a little bit later on."

More focus has centered on Sexton's style of play, playing right to the gainline, in light of further punishment against Scotland, but don't expect the 33-year-old to change any time soon.

"When you play flat on the line, you are going to get hit," Murphy said. "Obviously we don't want him off the pitch, but there is definitely a fine line between what is fair and what isn't fair

"If he changes, he is not the same player he was. He doesn't create the same holes for players that he creates for other people. Then there is no point in having him.

"It's a two-fold thing really. The idea of him changing his game so that he can stay on the pitch doesn't really fit.

"He needs to play the game he feels is best. He is a confrontational type of character, he wants to play on the gainline. He wants to create space for others. I can't see that changing."

Murphy laughed off the suggestion that ultimate competitor Sexton wouldn't be pleased to be part of a squad rotation decision, insisting the man in possession of the jersey is well aware that sometimes changes need to be made for the betterment of the team.

Carbery is yet to start a Six Nations game and the coaching team didn't offer any clues as to whether he will get the nod for Sunday's encounter in Rome.

"It would be a natural progression for him at this stage [to start]," Murphy said. "Obviously he came on early against Scotland and he probably had a bit of a shaky start and built himself into the game.

"Those opportunities, when they do come along, he needs to grasp them with both hands. We will have to see where that goes this week."

With Kieran Marmion out of the equation, Ulster's John Cooney has assumed the role of back-up to Murray, scoring a consolation try against England and getting on for the final three minutes at Murrayfield.

The Munster scrum-half didn't play for almost five months due to a neck complaint and is building his way back to form.

A try scorer against the Scots, the precise box-kicks, crisp passing and game management have been slightly below his best and Murphy says it is only natural given his time on the sidelines.

"I think he is progressing well. A late start to the season is actually quite difficult for a lot of players and Conor is no different. 

"Everyone around him can make things much easier for him, take the pressure off him. Everyone knows he is a world-class player. 

"The thing is to try and get him back into that, where he is feeling good about himself and players around him are taking pressure off."

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