The Red Devils fell behind at the Stadium of Light in the fifth minute when Craig Gardner fired home.
But on his first Premier League start, the 18-year-old Januzaj powered in Patrice Evra’s cut-back before sealing the win with a stunning volley in a six-minute spell after half-time.
The game prompted a flurry of activity on Twitter and here are our favourite updates, in chronological order.
Aston Villa’s Gary Gardner (@22Gards) is thrilled to see his older brother give the Black Cats the lead: “Boooooom that’s my bro!”
Celebrity Arsenal fan Piers Morgan (@piersmorgan) can’t help but poke fun at some of the United players as the Red Devils fall behind: “Oops. @rioferdy5 @WayneRooney @persie_official”
Former Northern Ireland international Norman Whiteside (@NormanWhiteside) questions the United captain’s defending: “Nemanja??????? :(”
England legend Gary Lineker (@GaryLineker) chimes in: “Gardener digs a deeper hole for Moyes to climb out of.”
Ex-Black Cats boss Peter Reid (@reid6peter) refuses to get carried away: “What a start ! Long way to go. Prefer one in the last minute.”
Team GB’s Dai Greene (@DaiGreene) pokes fun at Twitter after United fall behind: “Is #MoyesOut trending yet?”
Former Sunderland man Michael Gray (@mickygray33) has been impressed by the Black Cats’ Italian striker: “Giaccherini having a great game… #safc 1,0 Gardner”
Ex-France international Louis Saha (@louissaha08) hails David De Gea after the United goalkeeper does brilliantly to deny Emanuele Giaccherini: “What a save!!!!! #DeGea”
Ruud Gullit (@GullitR) praises the Black Cats’ work-rate at the Stadium of Light: “Very impressed about the work rate of @SAFofficial but can they hold on?”
After United equalise, Norwich City’s Anthony Pilkington (@Pilkington_11) is stunned by Januzaj’s brilliant volley to put United 2-1 up: “Wow this januzaj is some player! What a finish that is!!! #Naughty”
West Brom’s Steven Reid (@stevenreid12) is impressed: “Oh my word #wonderkid #MUFC”
Liverpool legend Dietmar Hamann (@DietmarHamann) praises the young Belgian: “Januszaj looks a bit special for United,done more in a half than all the other wingers all season.I give him benefit of doubt for the dive.”
Lineker (@GaryLineker) wants Januzaj’s parents to make an exception this evening: “Adnan Januzaj should be allowed to stay up past his normal bedtime to watch #MOTD tonight.”
And Manchester United coach Phil Neville (@fizzer18) is pleased with the three points: “Good day good win-fans were brilliant tonight well done. Time to go home and c the kids looking forward to a Sunday morning lie in!!”
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