Goalkeeper Craig Gordon has decided to leave Celtic as he considers an offer from Hearts.
His contract with the Premiership champions had expired, and he has rejected the chance to extend his six-year stay on reduced terms.
Hearts have offered Gordon a two-year deal to return to the club and he confirmed others have shown interest.
The 37-year-old told BBC Scotland on Saturday he wants to play regularly so he can represent Scotland again.
“At 37, and with a few years in me yet, I just want to play the game I love, and have played for 20+ professional seasons,” Gordon wrote on Instagram.
“Football can make for difficult decisions, but I’m looking forward to the next chapter and challenge.”
Gordon began his career with Hearts before moving to Sunderland in 2007 for £9m, which was a British record fee for a goalkeeper.
He joined Celtic in 2014 after two years out of the game with a knee injury, and went on to win five Premiership titles, five League Cups and three Scottish Cups.
But last season he made just six appearances, four of which came in Europe, as Fraser Forster became Celtic’s first-choice goalkeeper.
“The last six years have been the most successful period of my professional career, and I would like to thank everyone who has played their part in making this possible,” Gordon added.
“The club, for initially taking a chance on someone who hadn’t played in nearly three years.
“And to Woodsy [Celtic goalkeeping coach Stevie Woods] for encouraging me to make the move in the first place, and for training me ridiculously hard ever since.”