Ireland number eight Jamie Heaslip has announced the end of his playing career in order to "ensure my future wellbeing".
The Leinster number eight has not played since being struck by a lower back injury during the warm-up of last year's Six Nations victory over England in Dublin, a week after completing 80 minutes against Wales.
After two unsuccessful operations, the most recent in late October, the 34-year-old British and Irish Lion has been forced to retire on 95 caps.
"Time will get us all but it has cornered me earlier than I had hoped," Heaslip said in a statement.
"Every professional sportsperson always hopes to be able to leave their chosen sport on their terms but too often that's not the case.
"I have had to take on board the medical advice that I have been given and after talking to Sheena and my family I have taken the difficult decision to retire with immediate effect in order to ensure my future well being.
"I'm very proud to finish my career as a one club man having played amongst some of the best in the game, who are all like a family to me.
"I've had the time of my life on and off the rugby pitch but now it's time for the next chapter."
Heaslip was a skilful back row known for a robustness during a relatively injury-free career and leaves the game having won three Six Nations titles and the 2009 Grand Slam.
"Jamie was utterly professional, driven to succeed and a leader with the actions he delivered," Ireland head coach Joe Schmidt said.