London Irish have signed former Saracens second row Kieran Roche until the end of the season.
The 23-year-old, who had been on trial with the club, was recruited following the ankle ligament injury sustained by Ryan Strudwick.
London Irish managing director Conor O'Shea said: "We needed to augment our second row resources following Ryan's injury. We are pleased to have been able to recruit a player of Kieran's ability and experience".