Celtic need to appoint a director of football before they select a new manager, says the club's former assistant John Collins.
Neil Lennon resigned last week and his assistant John Kennedy is overseeing the first team.
Former Celtic player Collins was Ronny Deila's assistant from 2014-2016.
"Every big club in the world has got a director of football in place first," Collins told BBC Radio Scotland's Sportsound.
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Deila and Collins won three trophies, including two Scottish Premiership titles, and Collins has also been a director of football at Livingston.
"The director of football has got to help choose the manager so the manager's his man and there's a relationship between the manager and the director of football that's so tight," Collins added.
"The most important thing is they have the director of football in place before a manager so the director of football is in the process with the owners, the board helping them select the right type of manager for the type of football the club's looking for."
'Celtic cannot be run by two people' - analysis
Former Celtic general manager Jock Brown on Sportsound
A club of the size of Celtic cannot be run by a chief executive and a manager/head coach. There has to be someone else in there involved in the football side of the business.
In an ideal scenario you want the chairman, the chief executive and the sporting director/director of football all agreeing on who the appointment should be, all having met the new head coach/manager and the head coach/manager having established that he thinks that he can work with them all. Not easy.