Ospreys have signed Cardiff Blues back-rower Ieuan Jones on a one-month loan following injuries to Morgan Allen and Joe Bearman.
Both forwards were injured during the Ospreys' 34-6 Champions Cup defeat to Northampton on Saturday.
Allen has suffered "significant ligament damage", while Bearman has an injured groin tendon.
"We've had no option other than to bring in someone on loan," said Ospreys rugby general manager Andrew Millward.
Ospreys are already without Dan Baker and James King, who are on international duty with Wales, while fellow back-rowers Tyler Ardron, Olly Cracknell and Tom Smith are all out injured.
Allen and Bearman have undergone scans to reveal the extent of their injuries.
Ospreys medical performance manager Chris Towers expects both players to have "lengthy spells on the sidelines".
Jones, 21, has yet to make his debut for the Blues since joining from the Dragons in May 2014.
The former Wales Under-20 international has found his path to the first team at the Arms Park blocked by the likes of Manoa Vosawai.
But following injuries to Allen and Bearman, Jones could be included in the Ospreys squad to face Connacht on Friday 31 October.
"He's a ball carrier with considerable experience for his age," said Millward.
"We are looking forward to seeing him taking this opportunity and making an impact in an Ospreys shirt."