“Leigh is in possession of the Celtic striker’s jersey – that goes without saying.
“He had a strong finish to the domestic season and it is up to him to keep hold of that shirt.
“He is at a fantastic club, knowing the team is dominating games and create chances.
“You don’t want to leave this club. So I told him he had to change and be more professional. He had to eat, sleep and drink like a real football player if he wanted to be a first-team regular at Celtic.
“It wasn’t just me as Ronny Deila was constantly on his case.
“Leigh looked me in the eye and told me: ‘I am going to change and do all that because I never want to leave this club’.
“All credit to him because he has done just that. I was always hopeful when Leigh said those things he would actually change.
“As a coach you always want players to make a difference to the way they live, eat and sleep because you want them to get better and make the most of their ability. Leigh has proved to himself, the coaching staff and his team-mates he could do it at Celtic.
“The key for Leigh now is to maintain it and not be happy where he is. He has to keep trying to get better.”