On Thursday night's show Newman let loose on Keenan, attacking his credentials as a ruck coach.
Keenan, a Geelong Advertiser columnist, said yesterday he had spoken with his solicitors and that they would soon issue a writ.
``What he said was a character assassination,'' Keenan said.
``He's impugned my reputation as a person and as a ruck coach and as a sporting commentator.'' Keenan, whose ruck coaching has been used by All Australian ruckmen Steven King and Spider Everitt, is most upset by being labelled an imposter.
``I've never been an imposter as a footballer, as a person or as a coach,'' Keenan said. ``That's what really hurts me, to say that.''
The spat between the two football identities also comes after Keenan focused on Newman in his weekly Addy column on Tuesday.
In the column Keenan described Newman as a ``goose'' after he appeared on the Footy Show sporting a windsock and blinkers in a parody of Chris Grant's goalkicking woes.
He also said Newman, who was this week inducted into the AFL's Hall of Fame, should also be in the Hall of Fools.
Newman said yesterday he had only been responding to an article when he took aim on The Footy Show.
Newman yesterday described Keenan's article as a ``gratuitous piece of slagging from a man who who hangs his hat on slagging people''.
He said he was bemused by Keenan's threat of legal action.
``He's speaking to his solicitor is he, well what a joke,'' he said. ``I mean, this is the thrust and parry of people who are in the media and he's taken exception to that?
``He's said plenty of things that I've taken exception to, but I would never ever think of speaking to my solicitor about anything at all. Unless he said I was a pedophile or a thief, anything else goes.
``Crackers is a great bloke and a friend of mine but it's a bit of live and let live.''
On the Footy Show Newman branded Keenan a ``fool'', an ``imposter'' and a ``buffoon''.
``Crackers is a fool and to see a man like Steven King being reined under his wing is just a disgrace to the football world,'' Newman said.
``In the interest of the club please leave and give Steven King a chance to resurrect his career.
``He (Keenan) is an imposter. He stands on the boundary, knows nothing and thinks he knows everything.''
Keenan yesterday called King, who he coaches on a voluntary basis, and told him not to answer his phone to avoid being detracted before today's match against the Bulldogs.