Perhaps Andy Farrell's only selection headache against Scotland is whether he starts Conor Murray or Jamison Gibson-Park at scrum half, according to The Independent's Ruaidhri O'Connor and former Scotland international Andy Nicol.

Ireland head into their final pool stage clash off the back of a rest week, having beaten South Africa in Paris a week earlier. This rest week came at the perfect time for the World No. 1 side, allowing the tired bodies to recover ahead of their final push for World Cup glory.

While Andy Farrell has rotated his squad slightly each week, he has not made wholesale changes to his first choice XV. One position that has rotated each week, though, has been scrum half, with Jamison Gibson-Park starting Ireland's first and third games, with Conor Murray starting in their second.

Now, with all on the line against Scotland, O'Connor and Nicol discussed which of the two form halfbacks should start against the Scots.

Murray is in 2016-level form

Speaking on Wednesday Night Rugby, O'Connor explained why he would start the Munster scrum half over his Leinster counterpart.

"It's more about Conor Murray and how well he's playing," O'Connor said. "If Andy Farrell picks Jamison Gibson-Park, it doesn't weaken Ireland at all.

"I'm just a big believer in backing form, and if a player is showing really good form like Conor Murray is, I think get him into the team.

"He's currently playing at a level that we haven't seen from him... close enough to the 2016 best of Conor Murray, which we hadn't seen for a long time.

"I do think the kicking game has been very important, and he's a better kicker than Gibson-Park. Scotland are vulnerable in the back field, they showed that against South Africa.

"If you put Gibson-Park on the bench, then you get him to just absolutely go up through the gears after 60 minutes against a tired team."

It depends on Ireland’s tactics

For Nicol, who joined O'Connor on Wednesday Night Rugby, Farrell is in a strong position to pick the halfback that suits the style he wants to play against Scotland.

"If they want to play with the really quick ruck speed, then Gibson-Park is the man for that job," Nicol said. "He actually creates a lot of that ruck speed. He's better than Conor Murray at doing that.

"If the game were to slow down, you'd want Conor Murray on the pitch. If you want the game to be fast, then Jamison Gibson-Park is your man. So, it's really a tactical decision for Andy Farrell to make.

"I think he'll go Gibson-Park. You still have to go with your gun team, and I think Gibson-Park is in it. In many ways, I'd prefer Conor Murray to play, because a slower ruck speed means that Scotland are getting their hands on the ball and slowing Ireland's ball down a bit.

"It's a great quandary for Andy Farrell to have."

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