SUNDERLAND: 20. Keiren Westwood 12. Ondrej Celustka 16. John O'Shea 29. Valentin Roberge 14. Jack Colback 8. Craig Gardner 56' 33. Lee Cattermole 4. Ki Sung-Yueng 74' 23. Emanuele Giaccherini 17. Jozy Altidore 11. Adam Johnson 64' Subs: 6. Cabral 7. Sebastian Larsson 56' 10. Connor Wickham 74' 24. Carlos Cuellar 25. Vito Mannone 27. Dong-Won Ji 64' 31. Fabio Borini
MAN UTD: 1. David De Gea 2. Rafael 86' 4. Phil Jones 15. Nemanja Vidic 3. Patrice Evra 16. Michael Carrick 23. Tom Cleverley 17. Nani 77' 10. Wayne Rooney 44. Adnan Januzaj 77' 20. Robin van Persie Subs: 11. Ryan Giggs 12. Chris Smalling 86' 13. Anders Lindegaard 14. Javier Hernandez 19. Danny Welbeck 77' 25. Antonio Valencia 77' 26. Shinji Kagawa
The 18-year-old Belgian winger, who had earlier been booked for diving, dragged a misfiring United back into the game with a calmly-taken 55th-minute equaliser and then smashed a dipping volley past keeper Keiren Westwood to win the game just six minutes later.
On an afternoon when United were far from their best, they were all but taken apart by the bottom-of-the-table Black Cats before the break with Craig Gardner's fifth-minute opener setting the stage for a concerted assault by the home side.
But David Moyes' men, who were facing a third successive Barclays Premier League defeat for the first time since December 2001, responded in the second half and eventually earned their reward.
Defeat left Sunderland with just a single point from the 21 they have now contested, and watching owner Ellis Short knowing he needs to find a replacement for Paolo Di Canio sooner rather than later.
Interim head coach Kevin Ball could have been forgiven for sending his team out simply to batten down the hatches and attempt to deny United anything in a bad to halt a run of three home defeats in the league.
However, the 48-year-old, who guided the Black Cats to a 0-0 draw at Old Trafford during his last spell in temporary charge, decided attack was the best form of defence and went for it from the off.
It took the hosts just five minutes to get their noses in front, although the goal arrived courtesy of some calamitous defending which rather set the tone for United's first-half display.
Emanuele Giaccherini tricked his way past Patrice Evra on the Sunderland right all too easily and fired in a cross which Phil Jones thumped straight at team-mate Nemanja Vidic.
The Serbia international could do little more than present the ball to the fast-arriving Gardner, who drilled a low shot across keeper David de Gea and into the bottom corner.
Few inside the Stadium of Light expected anything other than a ruthless fightback from the visitors, but United's efforts to get themselves back into the game were subdued at best.
Januzaj fired in a series of shots from distance, most of which were blocked by a defence in which the recalled Valentin Roberge in particular proved impressively stubborn, while Wayne Rooney, back in the starting line-up after recovering from a shin injury, carelessly ran into an offside position as he attempted to get on the end of Evra's 14th-minute cross to the near post.
But Moyes' men were astonishingly fragile at the back, where Jones in particular was found wanting on more than one occasion, and the Black Cats could have gone in at the break with a significantly bigger lead to defend after it.
Gardner made the most of the defender's indecision to run in on goal once again with nine minutes gone, but with the unmarked Jozy Altidore pleading for a cross, he delayed and Jones managed to recover.
However, it was De Gea who came to the rescue 11 minutes before the break when he somehow managed to claw away Giaccherini's goal-bound header with a save of genuine quality.
Keiren Westwood was called upon to beat away Nani's 41st-minute shot, but Giaccherini might have doubled Sunderland's lead in the final minute of the first half when he was presented with another golden opportunity by Adam Johnson's run through a porous United defence, only to sky his effort high over the bar.
United's desperation was summed up within three minutes of the restart when Januzaj collapsed in a heap as he went past John O'Shea inside the penalty area and was promptly booked for diving.
But the Belgian was not to be denied and his industry paid off seven minutes later when he played the ball out to Evra on the left and then worked his way into the penalty area to meet the Frenchman's cross with an assured finish.
Westwood had to get down well to keep out a 58th-minute Robin van Persie snapshot, but he was powerless to prevent United taking the lead three minutes later.
O'Shea got his head to Nani's right-wing cross and the ball dropped nicely for Januzaj, who gleefully dispatched it into the bottom corner with a sweet left-foot volley.
Van Persie should have made sure at the death after being played in by substitute Antonio Valencia, put prodded his effort wide of the upright.