Neil Lennon's bad language has landed him in hot water with the Scottish Football Association after he vented his anger during Celtic's 1-1 draw at St Mirren Park on Sunday.
Lennon has been accused of misconduct by the SFA's compliance officer after an apparent "failure to behave in a responsible manner as an occupant of the technical area by repeated use of offensive, insulting and abusive language''.
Pitch-side microphones appeared to capture Lennon swearing at St Mirren captain Jim Goodwin after a tackle near the dugout. Lennon has not been offered a fixed suspension and has seven days to respond to the notice of complaint, with a hearing date pencilled in for April 18.
The charge relates to a verbal exchange in the 75th minute of the Scottish Premier League match, after Goodwin put in a strong but fair challenge on Celtic's Dylan McGeouch. A voice which appears to be Lennon's was heard to say: "Well done, Jim, think you're a hard man, eh?'' before the swearing began.
Goodwin, who played alongside Lennon at Celtic, had brushed off the incident before the SFA took action. Goodwin said in the Daily Record: "McGeouch had just come on, I flew into a tackle with him and Lenny was just protecting his player. He barked a few words at me and I have no problem with that.
"I'm just happy the Sky microphone wasn't close enough to pick up my unprintable reply or else I'd be in trouble myself. Lenny probably wouldn't have spoken to me again if he had heard my reply but it was all a top bit of football banter and I have no problems at all. We are both passionate men who want to win and both of us are bad losers.''
After the match, Lennon described Bobby Madden's display as the "most appalling refereeing performance I have seen for a long, long time''. Madden made several dubious major decisions, including the award of a penalty following an incident that saw St Mirren forward Esmael Goncalves issued with a notice of complaint for alleged simulation.
Celtic have also notified the SFA of their intention to appeal against Victor Wanyama's red card in the game, with confirmation of an appeal hearing expected later.
Information from the Press Association was used in this report