The 33-year-old has enjoyed a glittering career which has seen him play in some of football’s most prestigious competitions, including the Premier League and UEFA Champions League.
He may be remembered most fondly for the 155 appearances he made for Reading between 2007-2015.
Karacan joined Boro ahead of the 2022/23 season and made 15 appearances in total.
He scored his only two goals for the club in their 4-2 win over Guiseley last November.
In a lengthy message posted on Instagram, he said: "It’s taken me a little while to be able to write this but I’ve officially retired from football.
"There are so many people I need to thank for my time playing football. The fans, your support always meant the world to me and I’ll never forget it.
“My team-mates, some of whom have become my closest mates and more importantly golf partners. All of the managers, coaches and staff I’ve had the pleasure of working with and learning from.
"I grew up just wanting to kick a ball about, I could never have imagined doing it for a living, scoring in the Premier League or standing there for my dad’s favourite team in Turkey and humming away to the Champions League anthem.
"For now I’m not sure how I will fill the football-shaped hole but I’m excited for what lies ahead.”
Photo credit: Radcliffe
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