Johnny Sexton and Keith Earls remain serious doubts for Sunday's World Cup quarter-final against Argentina at the Millennium stadium.

"Johnny did about 3.5 kilometres of running, that's a positive," said Ireland scrum coach Greg Feek.

“We’re quietly confident, we’ll see how he goes on Friday.”

Sexton has an abductor (groin) strain that forced his replacement, for Ian Madigan, just 25 minutes into last Sunday's victory over France.

The assumption is he will attempt to train on Friday.

“We’re going to see how (Earls) goes, we’re looking after him a bit and it’s not too bad, we’ll see how he goes on Friday as well. He’s just a bit battered, that’s all. It’s not too bad. At this stage, you want to do the best to make sure everyone is fit and available.

“Earlsy’s pretty good,” Feek added later. “His body’s pretty good.

We’ll just wait and see again, as the week goes on, we’ve a day off tomorrow and on Friday we’ll have a good session and we’ll go from there.”

Similar utterances were made about Jared Payne, initially diagnosed with a bruised foot but upgraded to a fractured foot after a second scan.

Luke Fitzgerald is poised to come into the centre alongside Robbie Henshaw.

The usual Joe Schmidt edict is a player must train early in the week, in order to immerse themselves in the game plan, if they are to start on the weekend. Due to the number of walking wounded, that has been shelved this week.

Friday’s captain run at the Millennium stadium seems like the deadline for selection.

"When you start to accumulate a number of games in a row, in the Six Nations you usually get two and a week off, in November you get three but you can still mix it around," said Feek.

“But here, it’s do or die type stuff, so there might be some allowances around a few things, especially with our medical staff and our S&C, they’ve a good feel on things as well.”

Meanwhile, Ireland are extremely unlikely to appeal Sean O’Brien’s one week ban for striking Pascal Pape. There is a 48 hour window in the unlikely scenario that they do opt to appeal the decision, and a hearing could be convened as late as Saturday.

“We’ve got guys sitting there raring to go, some guys haven’t played much and it’s always been our mantra that you’d have heard regularly about the collective. That’s something this team prides itself on, so we’ve got to get our head down and get organised for the week,” Feek added.