Celtic have set themselves up for a fall by allowing Kristoffer Ajer to leave without a replacement, claims Mark Wilson.
The Norwegian defender looks set to be closing in on a move to Brentford having made clear his desire to leave Celtic Park earlier this summer as he entered the final year of his contract.
The move will see Celtic snap up a reported £13.5million for the 23-year-old, but leaves them short of experience in the centre-back role.
While Carl Starfelt is being lined up as a replacement, the Glasgow giants are short on time to seal the deal for the Swede before the Champions League playoff with Midtjylland.
Pundit and former Hoops defender Wilson reckons this could be a misstep by the board if they leave Ange Postecoglou with 21-year-old duo Stephen Welsh and Osaze Urhoghide as his first choice pair for the blockbuster first leg.
The former Parkhead defender told Clyde 1 Superscoreboard: "They've left themselves desperately short in this department (defence).
"The Celtic hierarchy would have known this is the plan for Ajer. As Ajer said, he hopes Celtic would have stuck to the promise, so there is no surprises here.
"He has a year left and he was never going to sign a new deal.
"The head of recruitment went pretty early, as did the manager, so there was nobody to make these decisions. Peter Lawwell couldn't just pluck a name out of thin air and bring him in.
"It's a domino effect. If you don't have a manager and a head of recruitment you leave yourself in this position.
"You leave yourself short and inexperienced at the back.
"Carl Starfelt has been rumoured to come. Whether that happens or not, Celtic need someone experienced in there who is commanding and could be relied upon.
"Ajer was that character. It's a big void, and another void.
"Your biggest and best player is going out the door and you haven't replaced him.
"Going into this European tie, and the league will come really quickly, you need to have a greater depth of squad to cover these positions.
"You could excuse them if this game popped up out of the blue, but this fixture has been pencilled in for a long, long time.
"It's just been too slow from everyone at the club.
"They've left themselves short of players and short of time, and there is only one way that will turn out for you in the Champions League."
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