It is remarkable that Celtic called upon 40 players this season. A further 7 were unused substitutes.
However, given the sheer volume of players used, it was a relatively small group that did the heavy lifting and saw Celtic progress past Group Stage European football and capture two trophies.
I usually use 900 minutes as the cut off for applying minutes in terms of having reliable reportable data. Only 19 players passed this mark all season.
These players formed the back bone of Celtic’s success under Postecoglou.

Hart played the most matches (54 – 1 more than Abada) and had the most minutes (4890).
Only four players past 4000 minutes – Hart, McGregor, Starfelt and Carter-Vickers.
Rogic made 50 appearances but completed only 2776 minutes.
Only 19 players played more than 20 matches and surpassed 900 minutes. This shows that it was a relatively small pool of players Postecoglou relied upon again and again.
Many players played bit parts and deserve to be remembered for their contribution to a redeeming season:

The message is Celtic need to replace Bitton and Rogic, and then decide how to flesh the squad to at least 25 trusted 1st teamers.
Of the backups, I will be surprised if more than 3 make an impact next season of any note.
For now, salute those who have brought such success and brace for another busy summer.