Wales hooker Richard Hibbard will miss this weekend's derby for the Ospreys against Cardiff Blues due to a hand injury.
Hibbard has a broken bone in his right hand that is set to keep him out until the new year.
The news means that Hibbard will miss another Welsh derby when the Blues play the Scarlets on Boxing Day.
The British and Irish Lions hooker announced earlier this week that he would be leaving the region to join Aviva Premiership side Gloucester next season.
Hibbard's injury is not expected to hinder his participation in the build-up to Wales' defence of their Six Nations title next year.
Meanwhile, Ospreys centre Andrew Bishop has also been ruled out with a back injury. Ospreys head physio Chris Towers said he is expected to be sidelined for around four months.