Hull KR centre Sean Gleeson has announced his retirement at the age of 26 after failing to fully recover from an assault outside a nightclub.
Gleeson, who joined Rovers on a three-year contract from Salford Red Devils at the start of last season, sustained a serious eye injury while being attacked by three men in Greater Manchester three months ago.
In a statement, the club said: "It is with deep sadness and regret that Hull Kingston Rovers can confirm Sean Gleeson has called time on his career with immediate effect.
"The Robins centre suffered a serious eye injury earlier this season and has been advised to retire from rugby league at the tender age of 26 following a meeting with medical experts last week."
Gleeson, who also played for home-town club Wigan Warriors, Widnes Vikings and Wakefield Trinity Wildcats, made just six first-team appearances for Rovers after being dogged by injury.
"It is with saddened regret that I have made the decision to retire from the great sport of rugby league," he said.
"Coming to terms with this news has been difficult, but I would like to thank my agent, Martin Shuttleworth, for his support and guidance during these hard times as well as (chief executive) Mike Smith at Hull KR for his support and understanding of the circumstances I have been going through.
"I would also like to say a big thank you to the Hull KR fans for welcoming me to the club and to Hull, where I have made so many friends in and out of rugby league.
"Lastly, I would like to thank (coach) Craig Sandercock for believing in me, giving me the chance to play for a club with such great heritage and for standing by me through the injuries that I sustained. I have learned so much from Craig and have massive respect for him."
Gleeson hangs up his boots having made 134 career appearances, scoring 37 tries, and he represented Ireland at the 2008 Rugby League World Cup.
Hull KR chief executive Smith added: "This is sad news for everybody connected to Hull Kingston Rovers and our thoughts are with Sean, his family and his friends at this difficult time.
"Although Sean's time with the club has been hampered by injury, he has always conducted himself with the utmost professionalism in a bid to get back on the field and for his career to come to an end in this fashion is very cruel.
"The club will continue to offer its full support to Sean in the coming days and weeks as he begins to look towards the future."