The Scottish club’s discussions with the former Bournemouth manager broke down on Friday after the management failed to give him assurances over his backroom staff.


There was also believed to be a disagreement over potential transfer targets, with Howe left unhappy and pulling out.



Caldwell admits that the development was a surprise for Celtic fans, but does not see it as a disaster as he feels there were still question marks over Howe.


However, the 39-year-old stressed the need for his former side to act quickly as they need to get on with their pre-season preparations.



“I think it is a big surprise to all Celtic supporters. It looked like the frontrunner”, Caldwell told Sky Sports.


“The club was quiet but there was no other names really in the running, but it seemed like a matter of time before he took the job.



“Obviously at the 11th hour it’s fell down and it’s not going to be, so they have to move on from that. I don’t think it’s a disaster.


“I think Eddie Howe still had a couple of question marks in terms of the size of Celtic and coming to a new league and country.


“They can assess the other candidates but need to move quickly.”


Former Australia boss Ange Postecoglou is now the favourite to take over at Celtic as the club search for a quick appointment.


Howe meanwhile could have options in England, with several sides on the lookout for a new boss.