Millwall striker Richard Sadlier has quit football after losing his battle with a hip injury.
Sadlier won one cap for the Republic of Ireland
The Republic of Ireland international has had two operations on his hip in the last 18 months and attempted a number of comebacks - the latest against Crewe and Stoke this season.
But the 24-year-old continued to suffer discomfort and has decided to hang up his boots.
"It got to the stage where every day I was getting pain in my back and my hip just doing the most basic of activities," he said.
"Eventually, I reached the decision that the longer I tried to play, not only was I doing more damage to myself, but the strain was becoming too much.
"I was building myself up for each comeback and then being bitterly disappointed when it didn't work out.
"I was told 18 months ago that it was possible that I wouldn't play again and at the time I refused to take that seriously and was convinced that I would.
"Whilst I did manage that, it never lasted for more than two or three games, and it just seemed that after all this time I hadn't made any progress and the symptoms were getting a lot worst.
"I spoke to the new medical people and it just made sense for me to stop now.
"The fact is that this does happen to footballers and unfortunately it has happened to me now."
Sadlier joined Millwall as a trainee in August 1996 and made 119 appearances, scoring 41 goals.
He won his single international cap as a substitute against Russia in February 2002.
"This is desperate for Richard," Milwall boss Mark McGhee said.
"I've managed at four clubs now and Richard Sadlier is the best young centre forward I've seen. He had the potential to go right to the top.
"It is a shame for him and for the game in general that he has had to retire."
Millwall chairman Theo Paphitis told the club's website: "This is a tragedy for Richard and a tragic loss for the
"He is a top-class player, a model professional and a thoroughly decent lad who deserved better than to see his career end at the age of just 24.
"We will now never know what he might have achieved in the game and we are just so sorry for him."
Republic of Ireland manager Brian Kerr paid his own tribute to Sadlier.
"It's very disappointing news," said Kerr. "It's a great shame that he cannot fulfil his undoubted potential."