Shane Duffy has thanked Celtic fans and teammates for helping him through a "tough year".
Duffy said farewell to Celtic on social media amid reports that an injury has ruled him out of the last two games of the Scottish Premiership season.
The Republic of Ireland defender endured a torrid time at his boyhood heroes after signing on loan from Brighton.
The 29-year-old scored in his first two appearances but soon suffered a loss of form and confidence as Celtic's season crumbled and their hopes of a 10th consecutive title slipped away.
Duffy posted a photograph of the high point of Celtic's campaign, them collecting the Scottish Cup following the previous season's delayed final in December.
The centre-back played 90 minutes at Hampden before Celtic clinched the trophy on penalties following a 3-3 draw with Hearts after extra-time.
He wrote on Instagram: "Grateful for the opportunity to get the chance to play for a club that many dream about doing.
"Thanks to the supporters and the players for helping me through a tough year on and off the field. Not many know what goes on behind the scenes .
"Time to hit restart button and get myself sorted. Celtic football club will always have a place in my heart."
Duffy has two years remaining on his Brighton contract.