Noel Whelan has suggested Celtic defender Christopher Jullien could be out with a knee injury for longer than nine months.

Speaking exclusively to Football Insider, the former Aberdeen striker warned it will take the 27-year-old a long time to recover his match sharpness when he returns to fitness.

The Frenchman has been missing since the end of December when he collided with the post at Celtic Park in the Hoops’ 3-0 win over Dundee United.

Manager Neil Lennon revealed on Friday the defender is expected to be out for between six and nine months and he has returned to France to undergo rehab on the injury.

Asked how big a blow it was for Celtic to have Jullien missing for the beginning of next season, Whelan told Football Insider correspondent Dylan Childs: “It’s huge.

“He’s one of the more established and experienced defenders they have there.

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“We saw when he did come back the difference that he made. He knows the football club a little bit better than other people.

“When you lose quality for that length of time and when you think about the time it’s going to take him to get back into the swing of things football-wise. It’s OK getting the fitness up but you need to get into the groove of your own game and the technical side of it.

“It’s going to be a long old haul for him and Celtic are really missing a player like that, given the season they’ve had.”

Jullien has played just nine Scottish Premiership games this term and Celtic did not lose a league game when he was in the side.

The Hoops kept six clean sheets in that time and conceded just three goals.

In other news, Frank McAvennie has been left very excited by Celtic’s deal for Liam Shaw after what he’s heard from Tony Pulis.