Manchester United were the latest team to be linked with the 20-year-old frontman who netted his 15th Hoops goal in the 4-0 win over Ross County in midweek.
“They knew they were coming into a coaching environment at a huge club which is going to extend them and test them under pressure.
“So, he’s loving and enjoying every minute of it. Boys such as Scott Sinclair, with a Premier League background, have come up here.
‘It’s a club that is a real privilege to either manage or play for. The boys are finding that out.”
He said: “This is a very very hard club to leave as a player. But in any market, in any job or any role, if someone offers you 100 grand a week and you’re on 40 grand a week, then you’re going to look at it.
‘And the reality is that, no matter if we are in the Champions League, there are going to be other leagues, including the English Premier League, that can offer money that will dwarf the revenue a club like Celtic can earn.
‘That’s the reality of it. It’s not downgrading anything. This is one of the great clubs of the world. But, at the blink of an eye, if a club can offer someone 100 grand a week, 150 grand a week, then players’ careers are short – and it’s right they look at it.
‘But what we have to do is create an environment that they absolutely love and, for the length of time they are here, maximise what we get out of them.
‘If they move on, then it also ensures that the club benefits. Then we have to have a process in place here in bringing in players consistently, so if we lose one we bring in another one.”
