After a busy summer of big-name signings for Celtic, the Scottish Premiership transfer window is now slammed shut until the new year.
Six permanent signings and four loanees arrived following Martin O’Neill’s permanent appointment in the summer, with Kasper Hogh, Camilo Duran and Haissem Hassan the highlights of Celtic’s summer additions.
Back-to-back defeats to Rangers meant the champions' unbeaten start to the domestic season was blown apart, and supporters are now hoping O’Neill’s men can return to winning ways as soon as possible and increase their two-point lead at the top of the division.
While the window is closed, the free agent market could still play a part for many other Scottish Premiership clubs before January, with several players still available on free transfers.
But how many free agents are Celtic stars of the past? Here are 8 former Celtic players available for free and searching for new clubs this season.
5. Nir Bitton
A competent performer in midfielder, or at centre-back. Bitton left Celtic in the summer of 2022 to sign for Maccabi Tel Aviv back in his homeland of Israel. Now 34, he was spent the last 18 months with FC Ashdod, but was recently released. He hasn't made a senior appearance since December 2025. | SNS Group Photo: SNS Group
6. Jason Denayer
Denayer had a memorable loan spell with Celtic, forming an outstanding partnership with Virgil van Dijk that saw the club win a league and cup double, and he went on to represent Belgium at several major tournaments. However, he has been a free agent for the last 18 months after leaving Saudi Pro League outfit Al-Fateh by mutual consent in January 2025. He is still only 31.
7. Scott Sinclair
Sinclair enjoyed a highly successful spell with Celtic between 2016 and 2020, winning 10 major domestic trophies. He played a pivotal role in the club's historic 'treble-treble' era under Brendan Rodgers, before exiting to sign for Preston North End. He returned to boyhood club Bristol Rovers in October 2022, but his time with the Gas ended last summer, and he's yet to find a new club. Now aged 37. | Getty Images Photo: Getty Images
8. Shane Duffy
Endured a disastrous loan spell with Celtic after joining on loan from Brighton in 2020/21, but appeared regularly for the Seagulls in the English Premier League upon his return. Went on to play for Fulham and Norwich City, but was released by the latter in the summer and is still without a club. | Getty Images Photo: Getty Images