Former Wales skipper Rob Howley has been forced to retire after failing to recover from a wrist injury.
After helping Wasps win the Zurich Premiership and the Heineken Cup last season, the scrum-half had a pin inserted in his right wrist.
But the bone failed to heal properly and Howley has quit on medical advice.
The 34-year-old had been hoping to tour New Zealand with the Lions, but is now expected to take up a coaching role with Cardiff Blues.
Howley first suffered the scaphoid injury when he was stamped on during Wasps' match against Perpignan on 1 February, but he played on until the end of the season and scored the winning try in the Heineken Cup final against Toulouse.
"It's a very sad and scary feeling to be told that your rugby career is over," said Howley.
"I had high hopes of returning to Wasps and even pushing for a place on the Lions squad, but unfortunately it's not to be.
"I've had a fantastic career, both at club level and internationally and would like to take this opportunity to thank everyone involved.
ROB HOWLEY HIGHLIGHTS
1970: Born 13 Oct, Bridgend
1996: Wales debut v England
1997: Makes Lions tour
1998: Made Wales captain
2001: Second Lions tour
2002: Retires from internationals, joins Wasps
2004: Wins Heineken Cup
"I would like to give something back to rugby. I have said that I would like to give coaching a go, but starting at the bottom and working my way up."
Wasps director of rugby Warren Gatland said: "Rob came here in the summer of 2002 and brought something special with him.
"His service to the club was outstanding and something we will always be grateful for. I would like to thank him for everything he's done and wish him well for the future."
Howley won 59 caps for Wales, skippering his country 29 times, and is widely regarded as one of the best scrum-halves the northern hemisphere has produced.
He was selected for the 1997 Lions tour to South Africa but suffered a discolated shoulder in a tour match and was unable to play in the Test series.
He played in the first two Tests of the 2001 tour to Australia before a broken rib ruled him out of the series decider against the Wallabies.
Australia scrum-half George Gregan, who lined up against Howley on the 2001 tour, said:
"Through my career, there are probably a handful of really great half-backs I
played against, and Howley would be one of them."