London Irish hooker David Paice will be sidelined for up to two months after breaking his arm in Saturday's defeat to Leicester Tigers.
Paice underwent surgery on Monday after the 20-11 Premiership loss at Welford Road, but is not expected to return for "a month or two", according to Director of Rugby Brian Smith.
"David had surgery on a pretty bad break so he will be a month or two out of action," Smith told BBC Radio Berkshire.
With the 30-year-old ruled out, Smith confirmed the Madejski-based outfit would now look to bring in a replacement on loan.
Meanwhile, Irish have secured the services of renowned scrummaging guru Phil Keith-Roach, having suffered and fallen short in that aspect of their play so far this season.
Keith-Roach ranks among rugby's most highly-respected scrum "doctors", having masterminded the set-piece during England's 2003 Rugby World Cup triumph.
"There is no one on the planet who knows more about scrummaging than Phil Keith-Roach, so he has come in and is working with us and is someone I would like to continue working with," added Smith.
"We have to put whatever resources we can into the problem as it is holding us back as a group. We want to be pro-active and do something about it.
"My firm belief is, it is 80% perception how we are being refereed at the moment, but is up to us to turn this around.
"Phil is coming in for the rest of the season and potentially beyond.
"He will work on small technical things with each player one to eight. He has looked at every one of our scrums this season, that is what he does."