Jamie Osborne, Jacob Stockdale, Tadhg Furlong and Ryan Baird have been ruled out of Ireland’s autumn finale against Australia.
Versatile Leinster back Osborne and Ulster wing Stockdale sustained groin and hamstring issues respectively during Saturday’s 52-17 win over Fiji.
Prop Furlong has not featured at all this month due to a hamstring problem, while lock Baird suffered a head injury in his country’s 22-19 victory over Argentina on November 15.
Speaking about Osborne’s injury, Ireland forwards coach Paul O’Connell told a press conference: “He’s a big loss.
“He’s very versatile on the bench obviously, he covers so many different positions and is growing and getting better all the time.
“It’s a shame he’s out. Hopefully it’s nothing too serious and he’s back to us soon.”
Saturday’s Dublin showdown with Joe Schmidt’s Wallabies will be Ireland’s final match before head coach Andy Farrell takes a break to lead next year’s British and Irish Lions tour of Australia.
The Six Nations champions began November with a 23-13 loss to New Zealand before returning to winning ways against Los Pumas and Fiji.
O’Connell also confirmed Connacht hooker Dave Heffernan, Leinster prop Jack Boyle and Ulster back-rower Nick Timoney have been released to their provinces.
