Sir Alex Ferguson's side had to come from behind three times before snatching the winner right at the death against a spirited Magpies side in a Boxing Day cracker at Old Trafford
James Perch gave the visitors a shock early lead, but Sir Alex Ferguson's side was level against the run of play through Johnny Evans midway through the first half. Evans then put the ball in his own in net, in a goal surrounded by controversy before Evra once more got United on level terms shortly after the break.
Papiss Cisse put the Magpies ahead for the third time in the second half, just moments before Robin van Persie found a third equalizer for the hosts.
Javier Hernandez spurned a number of chances but dramatically gave United the lead right at the death.
Sir Alex made five changes to the side which drew at Swansea, with Wayne Rooney the most notable absentee. Hernandez, Phil Jones, Nemanja Vidic, Paul Scholes and Ryan Giggs all returned to the starting lineup.
Alan Pardew, meanwhile, replaced the suspended Cheick Tiote with Gael Bigirimana, while Sylvain Marveaux came in for Jonas Gutierrez in the only other change.
The visitors looked up for it early on and found themselves ahead inside four minutes. Michael Carrick's mishap in the midfield allowed Demba Ba to fire a speculative shot at David De Gea, and the United shot-stopper could only push the striker's effort into the path of Perch, who tapped home his first-ever Premier League goal.
Newcastle continued its bright start with Cisse and Ba keeping the United's defense on their toes. Fabricio Coloccini nearly doubled the club's lead after 20 minutes when he nearly looped a header over De Gea, while the hosts failed to even register a meaningful effort on goal.
But the equalizer, against the run of play, eventually came five minutes later when Evans bundled the ball in from six yards after Tim Krul had originally done well to keep out Hernandez from close range.
United was only level for a matter of moments as the Magpies regained the lead four minutes later with a highly controversial goal. Danny Simpson had his shot deflected into his own goal by Evans but it was disallowed for offside, with Cisse judged to have been in an active position. However, referee Mike Dean reversed the decision after consulting with the linesman.
It could have been even worse for United going in at halftime as Marveaux rattled the crossbar just before the break with a superbly struck left-footed free kick.
Newcastle was on top at the beginning of the second period too, but was again pegged back in the 58th minute as Evra drove home United's first shot of the half. Krul could perhaps have done better as the defender's shot crept past him from the edge of the area.
The visitors again took the lead, though, this time via an emphatic finish from Cisse after fine work on the left flank from Gabriel Obertan. Amazingly, United was straight back in it two minutes later; Van Persie drew a good save from Krul before turning in the ball in at the second time of asking.
It was all United for the last quarter of the game as it desperately piled forward in search of a winner. Van Persie and Hernandez spurned numerous chances, with the Mexican coming closest with a header of the post.
In a frantic final few minutes both sides could have snatched all three points. Sammy Ameobi did brilliantly after coming on to hold the ball up and beat De Gea with a controlled low effort, but saw his shot come back of the foot of the post. While Hernandez once again wasted a golden chance with a close-range header hit directly at Krul.
But the Mexican wasn't to be denied for much longer, Carrick's excellently chipped ball found Hernandez in the box and he slid home United's winner in injury time.