Peter O'Mahony and Rob Kearney sat out Ireland's penultimate full training session before Saturday's Grand Slam clash with England yesterday.
ormally, failure to tog out on the Tuesday before an international would result in a player missing out at the weekend but Joe Schmidt may loosen his policy given the stage of the tournament and the stakes this weekend.
Last week, Johnny Sexton took a limited part in the session due to a glute issue but was selected in the team that beat Scotland and senior men O'Mahony and Kearney are likely to be given the same latitude at the end of an attritional campaign.
Still, it is a concern for Joe Schmidt as he prepares to name his team for the Twickenham clash tomorrow.
The head coach is managing the experienced duo's load after they picked up knocks against the Scots.
O'Mahony (pictured) was replaced after hurting his leg in a ruck early in the first half, while Kearney played 75 minutes before coming off for Jordan Larmour with an ankle issue.
Assistant coach Richie Murphy said that all 23 players who featured against Scotland are fit and available, dismissing concerns over Cian Healy's injury, but the duo will have to prove their fitness tomorrow morning to be sure of selection.
"Peter is OK, everyone who played in the game on Saturday will be fit and ready to play this weekend. He is the same as Rob Kearney," Murphy said.
"Rob is fine, it's just a case of managing his load.
"He picked up a couple of bangs during the game at the weekend and we are just easing him back into the week. He is perfectly fine and available for selection.
"He got caught a little bit on his ankle. The medics have looked at him, they are very happy with where he is at and we felt that just with Rob's age and stuff like that we have to look after him.
"Johnny trained fully this morning and is fine. We were managing him a little bit through last week but he has come through that process.
"He had a little bit of glute issue but had no issues after the game or after training today.
"He has been slightly restricted in his training load in (terms of) the previous week.
"He is in a good place, he trained today, he kicked today, he'll kick tomorrow and is building into Saturday's game with no issues."
Jordi Murphy would be the likely replacement for O'Mahony if he failed to make it after replacing the Munster skipper to good effect last weekend, while Jordan Larmour is next in line at full-back.
However, Ireland will give their starters as much time as possible to make the grade.
Otherwise, Schmidt is unlikely to deviate too much from the starting XV that beat Scotland.
He may look to freshen up his pack by bringing Iain Henderson into the team, while Jack McGrath could rotate in for Healy who took on a big toll in last week's game.
Murphy believes confidence levels are high ahead of the team's biggest test yet.
"I think all the guys are pretty confident with how we have planned things out, understanding their different roles within that," he said.
"When we look through the game we will see a hell of a lot of opportunities that we did not take, whether we didn't throw a pass, or different little things we could have done better.
"I don't think we will ever play a perfect game of rugby. But going forward to this Saturday, we are going to have to be pretty close to it to win in Twickenham."