John Hartson has urged supporters to think before they act after Scott Sinclair was at the centre of an unsavoury incident at Glasgow airport on Sunday evening.

In the aftermath of Celtic’s 3-2 win against Rangers at Ibrox, Sinclair was believed to the subject of verbal abuse for three Rangers supporters inside a lounge. It resulted in the three men being denied access to their flight and asked to leave but the incident highlighted an uglier side of the game.

And Hartson has called on fans of either side to be appreciative of the fact that players are entitled to the same rights as everyone else.

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“I have to say that I never experienced too much negativity when I was playing for Celtic,“ he said. “There was the odd shout in a pub or a restaurant or one or two disagreements but that was the extent of it.

“But there seemed to be a fair amount of things thrown onto the pitch towards players on Sunday and you need to have a bit of common sense.

“The vast majority of Rangers fans will be appalled to hear that their fans were behaving like that towards Scott Sinclair because it is embarrassing. It is a game of football, that’s it.

“I always hear the argument that punters pay their money and are entitled to shout and swear and say whatever they like but the bottom line is that there is still a way you need to behave. And if you think you can get away with it in a mob mentality inside a stadium then fair enough but when you are living your life and with your family then it is a pretty poor indictment of some people.

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“I think you need to call people out on it and tell them that there is a way that everyone needs to behave whether they like it or not.”

Hartson, meanwhile has insisted that Brendan Rodgers will not allow the Celtic players to down tools now that they have moved 9 points clear with a game in hand. There are nine league games remaining this season still to play and as Celtic go in search of an historic back-to-back Treble, Hartson is well aware that the Parkhead side will be preparing for the business end of the season as the chance to embark on a unique achievement awaits.

“You’ve seen the mentality,” said Hartson. “I think Brendan will want to do a bit of work with the defence because we could see the frailties there at Ibrox but he will also want them to kick on now as a team.

“This is when it counts. There is a huge semi-final coming up against Rangers and you want to go into that on the back of a really strong run of form. The players will enjoy a day or two downing tools and taking a breather but they are professional enough to know that the hard work starts again the minute they’re back at Lennoxtown.”