There are three unwritten rules for football journalists at post-match press conferences: don't use the words "wheeler" or "dealer" around Harry Redknapp, never look Roy Keane directly in the eye, and don't forget to put your phone on flight mode if you are using it as a dictaphone.
Forget the first rule and the press conference is over. Forget the second rule and your life is over. Forget the third rule and you run the risk of Neil Lennon getting up to high jinx with your significant other.
The Celtic boss showed his humorous side in a recent presser, choosing to take David Beckham's mobile phone schtick to another level by actually picking up the calls. "You're not going out tonight, Michael," he says to the journalist whose partner he just pissed off.
Not all managers take mobile phone interruptions quite so graciously. The aforementioned Roy Keane, for example...