Jeff Hendrick and Stephen Ward have missed the Republic of Ireland's latest training session as the Boys in Green continue their preparations for Saturday's World Cup playoff first leg against Denmark in Copenhagen.
Ward was rested, while Hendrick is having a scan on what has been described as a back or glute issue.
The Burnley midfielder started both of Ireland's qualifiers against Serbia and Wales last month, but limped out of the Claret's win over Southampton on Saturday.
“Jeff came off after about 60-odd minutes, he was having a bit of a problem and he’s still a little bit sore at the moment,” said Martin O'Neill yesterday.
“He’s said he’s improving so that’s good news. If the game was tomorrow morning he might struggle but he’s pretty hopeful and the medical team are hopeful.
“In terms of Stephen Ward, it’s just a matter of keeping an eye on his knee. It needs a little bit of rest now and then. I’ve got no real problem with that.
“If we have to walk through some situations rather than just do them as normal for the players in the next day or so, we’ll do so.”