Former Middlesbrough, Celtic and Preston North End defender forced to retire at just 29 through injury
Fisher was released by Middlesbrough at the end of last season following an injury-plagued spell at the Riverside.
Fisher, who won back-to-back Scottish league titles with Celtic, penned a two-and-a-half-year contract at the Riverside with former boss Neil Warnock describing him as “an athletic type who's desperate to come and do well with us."
The 29-year-old made his debut for Boro in the goalless draw with eventual champions Norwich City – one of 12 appearances to close out the 2020-21 campaign where the Teessiders would finish 10th in the Championship table.
Fisher, though, would have to wait over two years before making his next, and final, appearance for Boro, and in football, having suffered a serious knee injury during the summer of 2021, when coming on as a late substitute under Michael Carrick in Boro’s 1-1 draw with Coventry City in the final regular game of last season.
"I was really keen to get Darnell involved and back on the pitch. He's worked so hard," Carrick said following Fisher’s cameo in May.
"He's had an unbelievably tough run with a long, long time out and he's trained so hard and worked so hard. He's had different setbacks so credit to him, he's trained and trained and deserves it.”
Fisher was released by Boro in the summer at the expiry of his contract and despite reported interest in the defender from further down the Football League, has made the decision to retire from football.
Fisher informed people of his decision via social media when saying: "The time has come to hang my boots up due to my knee injury, I’ve tried everything to get back to full fitness but just not meant to be.
"Thank you to all my team-mates, clubs and the fans who have supported me over the years."