Huddersfield Giants half-back Luke Robinson has been forced to quit at the age of 31 because of a hip injury.
"My long-term mobility was greatly at risk if I continued to train and play the sport," said the former England international, who has also played for Wigan, Castleford and Salford.
"You never want to hear those sorts of words and it does shock you.
"But after a few days the message sinks in and you have to do what's right for yourself and your family."
Robinson, who made his Super League debut at the age of 17, said his focus was on "rehabilitation from an operation" but added that he wanted to continue working for the Giants in some capacity.
"I have come to regard this as my club and it's the only one I want at be at," added the Halifax-born Robinson.
"I want to put something back into them and the local community that has been so supportive of my time here."
Huddersfield managing director Richard Thewlis said the club would continue to support Robinson, who joined the Giants in 2008.
"This is a very sad day for all concerned," said Thewlis. "He has been an absolutely key figure in our rise from cellar dwellers to play-off regulars."