Neil Lennon singled out Leigh Griffiths for more criticism after substituting the striker at half-time against St Mirren.

Celtic lost 2-1 at home to the Buddies yesterday afternoon in the latest chapter of their disastrous season. The Northern Irishman swapped Griffiths for attacking midfielder Tom Rogic at the break, with two strikers - worth a combined £8.5million - in Patryk Klimala and Albian Ajeti still on the bench.

The manager addressed his recruitment after acknowledging questions of his summer signings' form but it was Griffiths who bore the brunt of frustration again when his boss pointed the finger at the striker for his lack of a telling contribution.

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We told recently how Griffiths was accused of being 'overweight and out of shape' by his manager as one reason why the Scotland cap had not been playing. The player refuted claims, insisting the only way he'd gain match fitness was by playing competitively regularly. 

But this weekend's defeat threw the argument up once again as Lennon detailed to BBC Sport. Asked about taking off Griffiths with two other attackers on the bench, Lennon responded: "I gave Ajeti half an hour today. You could look at Leigh and his contribution as well.

"It's not just about the players who have come in it's about some of the players who have been here for a while and just haven't performed."

Lennon challenged Griffiths to improve his fitness levels and the striker has been given more opportunities to play from the start alongside teammate Odsonne Edouard. He has scored seven goals in 20 appearances this term.

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But even after Griffiths scored in the Scottish Cup final back in December, Lennon still wasn't convinced on his fitness.

"I don’t know if he’s fit enough to do a full 90 minutes yet, " he said at the time. "That’s where I stand on it. I think he’s fit enough to play a chunk of games. He’s training every day but I think he can maybe push himself a little more. Griff has tunnel vision, he can be quite belligerent and he has great belief in himself. This isn’t him and I falling out over anything. I think he can get fitter.

"Maybe he thinks he can get fitter by playing more of the games but I think in between games or if he’s not playing as much he can do a little bit more. He may disagree with that but it’s just a difference of opinion, probably."