London Irish have signed tight-head prop forward Cai Griffiths from Welsh side Ospreys.
Griffiths, who can also operate at loose-head, has made over 100 appearances for the Welsh province.
He was part of the Ospreys side that won the Celtic League in 2005 and Magners League in 2007 and 2009.
"Joining London Irish is a chance to test myself in a gruelling competition week in, week out," said the 28-year-old England-qualified player.
"It is a challenge I am certainly looking forward to and one I am relishing. I have enjoyed nine fantastic years at the Ospreys and would like to thank the players and coaching staff for all their help during my time there."
Griffiths learned his trade under the tutelage of Wales and British and Irish Lions tight-head Adam Jones, and has developed into a powerful scrummager and key line-out lifter.
He is also effective in the loose and possesses good handling skills.
London Irish director of rugby Brian Smith said: "Cai is very solid at the set piece which is crucial when signing a tight-head prop.
"He is a direct replacement for Faan Rautenbach, who is leaving London Irish after seven years' service."