This ongoing issue caused him to miss the team’s opening game against Kilmarnock and now puts his participation in doubt for the upcoming Premiership clash with Hibernian at Easter Road this Sunday.

Despite speculation surrounding his future, Matt O’Riley was present at training, even amid reports that Brighton has agreed to meet Celtic’s valuation for him. Yuki Kobayashi, who has been linked with a move to St Mirren, also participated in the session, with centre-back partner Maik Nawrocki in training.

Callum McGregor was in training too, after he announced his retirement from international football.

Neil Lennon has responded to Rangers manager Philippe Clement’s comments post-match on the decision to award Celtic and Rangers each a penalty.

With Clement unhappy with the decision to award a penalty for the handball, Lennon was baffled by his reaction to the VAR intervention in the game.

Lennon said: [Sky Sports], “When I first saw it I though Johnston got the ball.

“You can look at it again and think there’s contact but it’s minimal.

“He runs into him. The way he goes down as well is embarrassing.

“I’m not happy with Philippe’s comments after the game – Goldson’s [handball] is not a penalty and that is – absolute waffle.”

Clement also revealed that he believed that the Rangers penalty was a clear foul on Fabio Silva, and the Portuguese striker should not have been booked in the first place.

He said: [Daily Record], “It is not getting a penalty. Everybody is really clear it is a penalty. He’s (Fabio Silva) been kicked against his knee.