Alan Stubbs has warned Celtic's new boss he faces the biggest rebuild project in Parkhead history.
And the former Hoops defender insists the size of the task awaiting Neil Lennon's replacement will only get bigger with every day that goes by before they make their long-awaited appointment.
Eddie Howe remains the frontrunner to take over in the east end of Glasgow but the former Bournemouth boss has made it clear he will not accept a new role until this summer as he waits to see what Premier League jobs open up.
"This could be the biggest rebuild in Celtic's history – that's how big the job is," said Stubbs, who won five trophies, including two league titles, during a five-year Parkhead spell.
"You're looking at a whole new back-four, a keeper, midfield players and strikers – plus squad players as well. That just doesn't happen overnight.
"Does it get harder with every passing day? I'd have to say yes.
"You have to bed these players in over the summer. The new boss has a huge job. I wish him all the best, whoever he is.
"When you look at where Rangers were three years ago then you've got to give their board credit for backing Steven Gerrard.
"Celtic could turn it around just as quick. But because of what's needed then it would be an incredible job if Celtic were to win the league next season.
"Rangers have got such momentum right now. They are in the position Celtic should have been in of only needing maybe two or three additions to improve on what they've got."
Stubbs is, however, relieved to have seen his old club have at least fast tracked new chief executive Dominic McKay's move to Celtic Park this week.
The former Scottish Rugby Union chief moved into his new office on Monday and will spend the next couple of months shadowing outgoing supremo Peter Lawwell as he gets to grips with the scale of the Celtic operation before taking over the reins himself on July 1.
However, Stubbs does not expect to see massive changes made immediately.
"Dominic McKay is going to be part of the rebuild," he said. "He's got a big part to play too. He has all the other roles to fill as well.
"Are the club going in the direction of a director of football? There's so many questions but probably not enough answers for the Celtic fans right now.
"They have completed part of the jigsaw by bringing in Dominic McKay early. That was a necessity. He had to come in before the summer as initially planned.
"But he will still be leaning on Peter Lawwell to show him how it works behind the scenes and it will take him time to get his ideas implemented to take the club forward."
::Stubbs was promoting exclusively live Premier Sports coverage of Hibernian v Motherwell this Saturday from 4.30pm and Rangers v St Johnstone this Sunday from 6pm. Premier Sports is available on Sky, Virgin TV and the Premier Player.
