Dean handed Feghouli a straight red after just 15 minutes for a lunge on Phil Jones that most observers judged to be a fair challenge worthy of a yellow at most, while some thought that Jones was the one who deserved the card.
RT if you think Mike Dean needs his eyes checked! pic.twitter.com/pwRz5pS1uJ
— Premier League (@Premierfanpage) January 2, 2017
The dismissal means that Dean has now shown five red cards this season, more than any of his refereeing colleagues.
The often controversial official was later slammed by fans and pundits alike for making himself ‘the centre of attention’.
And things didn’t get any better for West Ham later in the game when Zlatan Ibrahimovic scored United’s second goal from a clearly offside position.
Many people reposted the normally placid Garth Crooks’ infamous rant about Dean.
AMAZING: Garth Crooks verdict on Mike Dean. ?? pic.twitter.com/M0J3LNjlkZ
— SPORF (@Sporf) January 2, 2017
While former pros also chimed in.
Mike Dean is finished! So so so bad! He gets worse and worse every week. Take the whistle from him please!
— John Arne Riise (@JARiiseOfficial) January 2, 2017
Unfortunately not Gary, we didn't have Mike Dean reffing. https://t.co/A3plVPsOyL
— Jamie Carragher (@Carra23) January 2, 2017
What is going on with the refereeing in the premier league ? Mike Dean explain how that's a sending off ???????
— Chris Kamara (@chris_kammy) January 2, 2017
And of course Twitter was awash with witty comments and criticism of Dean.
Mike Dean started well here, really imposing himself on the game, but he's faded a bit and you've barely noticed him. Needs to step it up
— Barney Ronay (@barneyronay) January 2, 2017
Excited to announce our first signing of the transfer window.
At £20m, Mike Dean will prove to be an absolute bargain!
— José The Joker (@JoseZeJoker) January 2, 2017
Mike Dean would have disallowed Giroud's scorpion goal for dangerous play as he would die if a game or player was headline news without him
— Memz Dogi (@AFCMemz) January 2, 2017
I am actually surprised that no one in the stadium has run on to the pitch and slapped Mike Dean round his bald head
— Alex (@AlexScholes12) January 2, 2017
Until Mata and Rashford came on Mike Dean was the only one showing any sort of desire to win for Manchester United.
— SemperFiUnited (@SemperFiUnited) January 2, 2017
Mike Dean has the look of a man who'd enjoy telling you you could no longer order breakfast in a fast food place cos it's 1031.
— Phil Williams (@PhilWilliams) January 2, 2017
We’ll leave it for former cricketer Alec Stewart to have the final say.
Mike Dean likes to be the centre of attention at every opportunity. Top officials in sport are very rarely noticed.
— Alec Stewart (@StewieCricket) January 2, 2017