Shane Duffy has thanked Celtic for their support through a "tough year on and off the field".
The Republic of Ireland defender has left Parkhead to return to Brighton after a disappointing season on loan in Glasgow.
Derry-native Duffy was criticised for his performances as Celtic surrendered their Scottish title and he was also subjected to online abuse earlier this year.
Injury had ruled Duffy out of Celtic's remaining two league games and he goes back to Brighton where he still has two years left on his contract.
The 29-year-old lost his father just before joining the club he supported as a boy and he's praised Celtic's players and supporters for backing him.
"Grateful for the opportunity to get the chance to play for a club that many dream about doing," he said on Instagram.
"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."
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Shane Duffy has returned to his parent club @OfficialBHAFC.
— Celtic Football Club (@CelticFC) May 7, 2021