Leigh Griffiths will need to show “sensational” willpower if he is to save his career at Celtic, according to Michael Brown.

The former Premier League midfielder, speaking exclusively to Football Insider assistant editor Russell Edge, believes the Hoops striker has just a matter of weeks to prove to manager Neil Lennon he deserves to stay at Parkhead.

As quoted by Sky Sports, Lennon ripped into his striker for returning to training out of shape and insisted “if he wants to have a future here at the club, it’s down to himself”.

Brown believes Griffiths’ future with the Bhoys is hanging by a thread and insists that while he can save himself, he has got very little time to prove his worth.

“If you don’t make the pre-season trip for being out of shape, it’s a hard stance,” Brown told Football Insider.

“You have to rapidly – and I mean rapidly – show a work ethic like nothing else to actually turn that round in a matter of a course of weeks.

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“You can do it but your willpower has got to be sensational. He’s got to be training twice a day back at Celtic, getting himself in shape as best as he can.

“Then you need that bit of luck, with that over-training, not to get the injury, that’s the danger.”

Lennon insisted it would have been “pointless” taking Griffiths on the club’s pre-season tour to France after the Hoops squad returned to pre-season training.

The Bhoys kicked off their friendly fixtures with a 1-1 draw against OGC Nice on Thursday, Patryk Klimala netting the equaliser for the Glasgow giants.

In other Celtic news, Alan Hutton claims a barely-seen forward has leapfrogged Griffiths in the Parkhead pecking order.

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