NEIL Lennon's 212,000 followers will be relieved to know he has not lost his enthusiasm for, or interest in, Twitter.

The Celtic manager has posted over 5000 tweets over the past couple of years and is by far the most prominent Scottish football figure active on the social media site. Twitter remains a fertile vehicle for controversy, of course, even if the offence taken is often contrived and affected. Either way, the potential for footballers to invite trouble is endless.

Celtic have a policy of heavily fining players if they post anything which would damage the club's reputation, and in the interests of fairness the policy must apply to a prominent employee such as Lennon too. The manager was unimpressed by Charlie Mulgrew's decision to give his 83,000 followers a full-frontal picture of a pair of naked models. The male model's dimensions matched those of Mulgrew. At least in terms of their hairstyles, that is.

The episode was hardly a major scandal but the fact that many of Mulgrew's followers will be very young meant it was a foolish act by the 27-year-old. Lennon spoke about the matter yesterday and confirmed that the club had issued a general warning about behaving responsibly on Twitter. "Not just the players, but the players' wives as well," he said.

"I have told the players that anything damaging the reputation of the club will be heavily fined and we might have to stop them using it altogether. We have made them clear on that. There have been other episodes before this week where I have taken a dim view. We have made it pretty clear there is a certain line you can't cross. And Charlie putting up naked pictures wasn't one of his brightest ideas, I have to say. So he will get punished for that.

"There are a lot of good things I can use it [Twitter] for. For example, I did that 10k run the other week and raised a lot money. If I hadn't had Twitter I probably wouldn't have raised nearly as much. So there are benefits and, like everything else, there are drawbacks as well. I do have sympathy for the players because of how easy it is to get dragged into things. But the players should be experienced enough now to know what they can and cannot use on a public site."

Lennon made some Twitter-related headlines himself this week in an exchange with Rowan Vine. After Lennon claimed the Hibernian striker had made a "rugbyesque" tackle on Darnell Fisher, Vine replied with a tweet saying he might get "Alan Shearer to send him another size 9 Umbro Speciali in the dish". Lennon tweeted "did I read that right?" and the Hibs man subsequently apologised.

Lennon had little interest in revisting the matter. "It's not the end of the world. You move on. It's no big deal for me. He has backed down and apologised for it. He probably regrets it now and it was done in the heat of the moment. He might have had a pint at the time, I don't know. It's not personal. Do I accept his apology? Yeah, we move on."

Celtic move on to Partick Thistle tomorrow, with a 12.45pm kick-off, for the first Glasgow derby in the top flight this season. The defending champions and leaders remain unbeaten after nine league games although their remarkable home defeat to Morton means they will be idle when the Scottish League Cup quarter-finals take place next Tuesday and Wednesday. They are back on Champions League duty the following midweek.

"Ajax is looming but I have a free week next week," said Lennon. "I can look to give the boys a rest. But I'll still go strong with the players I have available because this is a game I want to win. I want to keep the unbeaten run going."

Mulgrew, Mikael Lustig and Biram Kayal have minor problems but should be available for Firhill. James Forrest injured ankle ligaments against Ajax and is unlikely to play. "It's a blow but it's nothing major. It's not a 'Jamsey Forrest type' injury - we actually know what it is this time and can deal with it.

"Partick Thistle have been excellent so far this season. They've taken to the Premier League very well. I think Alan [Archibald, their manager] has done a really good job. He was under immense pressure because Jackie McNamara had put down a real foundation there. But Alan has carried it on very well. They have some good footballers and they play well. I've been very impressed."

If he has been impressed by Thistle, though, the word hardly does justice to his thoughts on Virgil van Dijk. The Dutchman delivered another fine performance against Ajax and Lennon admitted it was likely richer clubs would try to buy him in January, even though he arrived at Celtic only in the summer. "Probably. But he is not for sale in January. Virgil has just come in the door, so let him progress. If he keeps going the way he is at the minute then it's inevitable there will be suitors for him, as with a number of the other players here. But that's not for the foreseeable future.

"There is an onus to sell sometimes if you don't have Champions League football. But now we are stable and don't need to sell anyone. The players look vibrant and are enjoying the football here."