Harlequins forwards Olly Kohn and Will Skinner have been forced to retire from rugby because of injuries.
Skinner has not played for over a year because of a neck problem, while a shoulder injury Kohn has been carrying is more severe than first thought.
Wales international Kohn, 32, scored four tries in 139 appearances for Quins after joining from Bristol in 2006.
Skinner, 29, joined from Leicester the same summer and played 149 times, scoring four tries.
Second row Kohn made his senior debut for Wales in this year's Six Nations game against Ireland, while flanker Skinner is a former England Under-19 and Under-21 international and has captained the England Saxons side.
"I'm disappointed to have to retire as I thought I had a few more seasons to go," Kohn said.
"I will look back at my time in rugby, especially at Quins, with many fond memories.
"I feel very lucky to have been part of a fantastic club with a great set of players and coaches that have helped me achieve some massive highs in my career."
Skinner commented: "Every player is devastated when the decision to retire is taken out of his hands, but I hope to maintain my strong relationship with the game and with Harlequins."
Director of rugby Conor O'Shea paid tribute to the pair and said Quins were "devastated" by the news.
"They have been and will always be remembered as true greats of this club and have inked their names indelibly into its history,
"Will has battled for the last year with his neck. However, Olly's retirement has come about more suddenly for him and Harlequins," he said.
"The club intends to keep both players involved in different capacities as part of its future plans.
"We are going to miss their personalities greatly, but they will still be around the squad as the club supports them with physiotherapy to alleviate painful aspects of their injuries, before helping them to focus on other areas post-rugby."