Paul O'Connell has been forced to retire on medical grounds.
The former Ireland skipper and Toulon lock has been unable to recover from the hamstring injury that he picked up at last year's World Cup.
"It is with deep regret that I have decided to retire from professional rugby following medical advice. I would like to take this opportunity to thank all at Rugby Club Toulonnais for their understanding and support over the past few months," the 36-year-old said in a statement.
"Since sustaining the injury at the World Cup I have been fully focused on returning to fitness and starting an exciting new chapter for both myself and my family in Toulon. Unfortunately this will no longer be possible."
During his career, O'Connell won the Six Nations on three occasions and the Heineken Cup twice in his stint with Munster.
