The offensive language used by North Melbourne AFL coach Alastair Clarkson has been revealed and the AFL has some big decisions to make.

There is not much doubt that the coach’s frustrations boiled over and his expletive-laden rant allegedly including the words ‘f...... c...’ was heard by those close to the Kangaroos bench, but who was it aimed at and how was it delivered?

Multiple sources have revealed that the foul language has not been denied by Clarkson, but the nature of the use is what will determine punishment by the AFL, as they scramble to piece together statements and context from those within earshot of the incident.

Clarkson was coaching from the bench during the Kangaroo’s 59-point defeat at the hands of Port Adelaide in Launceston when he was reportedly overheard shouting vile abuse following an umpire’s decision.

AFL legend Gary Lyon had some sage advice for the multiple premiership-winning coach on SEN breakfast radio in Melbourne today.

“I’ll be prepared to wait until they hand down the verdict, then if he’s stepped outside the boundaries again and he cops a two-week suspension because he’s abused an umpire then he is a slow learner,” Lyon said.

“If he’s just swearing in the general course of play, again be cognisant of where you are and who is around you.

“If you’re in the coaches’ box you can swear and go nuts. I’ve sat in enough coaches’ boxes to know what they’re like. If you’re down on the boundary, it’s a different story. I’m fully on board with being aware of your surroundings and the people who are in the vicinity. I’m a swearer and I need to be very cognisant of where I’m at.’’

AFL spokesperson Jay Allen confirmed the league were investigating the incident and whether the comments were directed to the umpires.

Allen added there would be updates after the enquiry, but if Clarkson is found guilty, he could face a minimum two-week suspension from the league.

Earlier this season, Clarkson was fined $20,000 for using a homophobic slur while remonstrating with St Kilda defenders Jimmy Webster and Dougal Howard after he concussed North Melbourne captain Jy Simpkin with a brutal high bump.

The incident comes as tensions boil with the Roos enduring a hapless season, yet to taste victory in 11 outings and failing to even get close, rooted to the foot of the ladder.

Clarkson and trouble have gone hand in hand since the four-time premiership mastermind returned for his second stint as an AFL coach, having been embroiled in the Hawthorn racism scandal for almost two years.