Players know what to expect from certain referees.
"Oh shit, we have Lee Mason tonight. He's a bit fond of a red card so stay on your feet." "Kevin Friend is in charge today so mind your language, he comes down hard on dissent." "We can get away with murder tomorrow, Anthony Taylor's in."
But when it comes to Mike Dean, it's likely very much a sense of "What's that fucking weirdo going to do today?"
The Wirral official, who supports Tranmere (fun fact), is undoubtedly the Premier League referee who best translates to viral video fodder.
Whether it's celebrating Spurs' goals or doing the most mundane of officials' tasks in the most theatrical fashion imaginable, he's often the star of the show when he takes charge of games.
https://www.youtube.com/watch?v=StRVqK7xgw4
Absolutely nobody picks up a ball like the spotlight-loving referee but not everybody's a fan of him.
He pissed off
Garth Crooks and he pissed off
Jamie Vardy.
But we can't get enough of him.
He was in charge of the Manchester derby in the EFL Cup on Wednesday night and with a game of that magnitude, there was always the danger that the occasion or the superstar players might be spoken about more than the man in the middle.
But this isn't Dean's first rodeo and he knows exactly how to get the Twittersphere talking.
Ahead of kick-off, he made the bizarre decision to give one of his assistants an almighty sniff which is, I'm sure you know, pretty fucking weird.
https://twitter.com/SportsJOE_UK/status/791356610325147648
And viewers were (kind of) divided on the typically untypical behaviour of the man, the myth, the attention seeker.
https://twitter.com/shannon_ae/status/791357327827996672
https://twitter.com/Em_MCFC/status/791356705829490688
https://twitter.com/iMemzy/status/791356672535035904
https://twitter.com/allentluke/status/791356484470865920
https://twitter.com/Jimfromtheblock/status/791356499251593216
https://twitter.com/Juppopovic/status/791356478862925824
https://twitter.com/paulpmcg/status/791355942931668996
https://twitter.com/HenryConnolly1/status/791355800262500352
https://twitter.com/gavinmitchell8/status/791355380819431424
https://twitter.com/LehmannsTerms_/status/791355048324464642
https://twitter.com/LiverpoolLegacy/status/791354944020484096
https://twitter.com/Pippa35/status/791354859203203072
https://twitter.com/adamheath/status/791354786570436608
https://twitter.com/KieranMoore_12/status/791354783798005761
https://twitter.com/mihirt25/status/791354672720273408
Polarising, eh?
Colm Parkinson is joined by Paul Rouse for a heated debate about Sky Sports' five-year GAA deal and an exclusive chat with AFL star Zach Tuohy on the new GAA Hour.