Former Celtic striker Frank McAvennie thinks that a new left-back will be the first thing the club will seek in the January transfer window.

Ange Postecoglou has been tested at left-back in recent weeks after positional regular Greg Taylor had to undergo shoulder surgery.

The Scot has missed the last 11 games in all competitions as a result, with the likes of Boli Bolingoli, Adam Montgomery and Josip Juranovic being used in Taylor’s absence.

Celtic have also been linked with Derby County left-back Lee Buchanan in recent weeks, with reliable reporter Alan Nixon believing that the Rams may sell in the next transfer window.

The Latest: McAvennie reacts

McAvennie was talking to Football Insider about the Hoops’ left-back ranks, which he labelled a ‘problem position’ based on the instability in the role in recent weeks.

He has tipped the club to remedy that in January by making a ‘quality’ left-back addition, saying:

“Left-back is the problem position.

“We just can’t seem to get it right. I don’t think Postecoglou is happy. Juranovic is a right-back but he plays left-back quite a lot of the time.

“Taylor is in and out and Bolingoli can’t get more than a couple of games even though he’s the best of the lot.

“That tells me Ange isn’t completely happy and I think a new left-back will be first through the door in January.

“I think we will spend, the money is there. The defence is definitely the problem.

“But the same centre-backs start every week and it’s usually Ralston at right-back.

“A top-quality left-back would improve us to no end.”

The Verdict: Over to Nicholson…

With no director of football or head of recruitment in place at Parkhead, you’d expect that the club’s winter window business will be down to interim CEO Michael Nicholson at this moment in time.

A left-back appears to be needed with Postecoglou so far struggling to find the answer without Taylor, so Buchanan could be a shrewd addition.

Wayne Rooney has tipped the Derby youngster to go on and play for England, and with the player out of contract at the end of the season, January could be the perfect time for the Hoops to make their move.

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