Ireland captain Caelan Doris will miss Saturday's Six Nations clash against Wales, with Ronan Kelleher and Tadhg Furlong also sidelined for the title chasers.
Simon Easterby's side head to Cardiff knowing they will be without Doris, who has a knee issue, while Kelleher and Furlong are struggling with neck and calf problems respectively.
Leinster back row Doris and hooker Kelleher were injured in the 32-18 rout of Scotland.
Prop Furlong has yet to appear in this edition of the Six Nations having also missed the November tests because of a torn hamstring.
Ireland, the only unbeaten team in the ongoing tournament, are optimistic that the absentees will recover in time for the crucial showdown with title rivals France on March 8.
"We're hoping they'll be available for France. They're just going through their processes that they do with the physios, but they're all making good progress," attack coach Andrew Goodman said on Tuesday.
The loss of Doris means Ireland will have a new captain for this weekend and Goodman believes they are blessed for options.
"There's some good leaders in the squad. The leadership group's been growing well over the past couple of years and there's a number of players who have captained their provinces, so we have some good options there," he said.
"You've got guys like Peter O'Mahony and Jack Conan who have captained their provinces.
"Dan Sheehan, Ringer (Garry Ringrose), JR (James Ryan), Cian Prendergast. There's a number of players with leadership experience."