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.
1. Jeffrey Schlupp
The former Crystal Palace left-back spent six months with Celtic, helping them win the 2025 league title, before signing for Norwich City on a free transfer last summer. He started just four times for the Canaries, though, and was therefore released by Phillipe Clement's men in June. He's still looking for his next club. | SNS Group Photo: SNS Group
2. Olivier Ntcham
Scorer of a famous injury-time winner in a 2-1 Europa League win against Lazio back in 2019, before leaving to sign for Swansea City shortly afterwards. He most recently played for Turkish top-flight outfit Samsunspor, but left when his contract expired in June. Recently linked to former club Marseille. | AFP via Getty Images Photo: AFP via Getty Images
3. Benjamin Siegrist
Signed on a Bosman free transfer from Dundee United, the Swiss goalkeeper couldn’t dislodge Joe Hart in the Celtic starting XI. Later signing for Rapid Bucharest, Siegrist didn’t find success there either and signed for Genoa on loan last season. Released upon his return to his parent club this summer, the stopper was recently linked to Juventus.
4. Boli Bolingoli
A major disappointment for Celtic, the left-back is remembered more for an off-field controversy than his on-pitch performances after he broke strict coronavirus quarantine rules by taking a secret trip to Spain during a two-day break. Bolingoli has since appeared for KV Mechelen and Standard Liège, but was released by the latter in the summer and is currently a free agent at the age of 31. | Getty Images Photo: Getty Images