The Swede turned home a Wickham cross to hand Giggs his first defeat as a manager but more importantly relegate Cardiff and Fulham, while giving the Black Cats hope of survivalSunderland stunned Manchester United at Old Trafford to take a massive step closer to Premier League survival.
A first-half goal from Sebastian Larsson, after good work from Connor Wickham, put the Black Cats ahead and Gus Poyet's side held on to secure a massive three points and in the process, relegate Cardiff and Fulham.
|VIEW FROM OLD TRAFFORD
|By Tom Marshall-Bailey
If Ryan Giggs did harbour genuine ambitions of landing the Manchester United managerial post in a full-time capacity, then his second audition for the role may have ultimately decided his fate. The 4-0 win over Norwich City last weekend merely served to paper over cracks which became clear for all to see once again at the home of the soon-to-be dethroned Premier League champions, a title they were rather undeservedly awarded by the stadium announcer prior to kick-off.
Sunderland arrived at Old Trafford riding on the crest of a wave having secured four points from trips to Etihad Stadium and Stamford Bridge respectively before a 4-0 win over relegation rivals Cardiff and they seized the initiative against a plainly woeful United side whose performance harked back to the David Moyes era then it did towards that of the Class of 92.
The Black Cats played with purpose and fully merited their 1-0 success, handed to them by Sebastian Larsson after typically slack United defending allowed man of the moment Connor Wickham to send in a cross at the perfect moment for Larsson, who cushioned an expert volley into the bottom corner as the Mackems held on to all but secure their Premier League status for another year while United and Giggs were left to contemplate a seventh home defeat this term, the first time they have managed that feat since the 1973/1974 season when they were relegated, a damning indictment of just how far this giant has fallen.
Defeats to Stoke and Newcastle respectively meant Fulham and Cardiff's fates were sealed, while Emanuele Giaccherini and Fabio Borini both hit the United woodwork in the closing stages.
Sunderland now hold a three-point lead over third-bottom Norwich City - who take on Chelsea on Sunday in their penultimate game - and a vastly superior goal difference.
Following a vibrant 4-0 win over Norwich last Sunday, interim United manager Ryan Giggs crashed back down to earth as a lacklustre display that allowed the visitors to claim a first league win at Old Trafford since May 1968.
A combination of illness and a minor groin injury kept Wayne Rooney on the sidelines - the only enforced change of five made by Giggs to his starting XI.
Former United defender John O'Shea almost turned Michael Carrick's 16th-minute cross into his own goal, while Nani fizzed over and Patrice Evra headed a 20th-minute corner into Vito Mannone's arms - though clear-cut chances were at a premium.
However, United's early lethargy remained and the travelling supporters were able to enliven a pensive Old Trafford atmosphere when Sunderland took a 30th-minute lead.
Darren Fletcher allowed in-form striker Connor Wickham to send over a cross from the right and Larsson sent a controlled volley into the bottom-left corner.
Sunderland winger Adam Johnson twice failed to capitalise on poor clearances from goalkeeper David de Gea as United staggered towards the interval in disarray.
United's pedestrian tempo continued after the break but Johnson switched off to allow the overlapping Evra into the box and his 50th-minute centre was superbly cleared behind by Wes Brown with Javier Hernandez poised to convert.
Nemanja Vidic headed wide when the resulting corner was worked back into the area and Sunderland suddenly found themselves defending perilously deep.
Activity in front of the away team's goal became somewhat frantic and Carrick and Vidic were both unable to force headers home when Phil Jones chipped towards the back post.
Sunderland almost made the points safe on an increasingly rare foray forward after 71 minutes - substitute Giaccherini hitting the post before Jack Colback crashed the rebound into the side netting.
By that stage, Giggs had also called for considerable reinforcements in the form of Adnan Januzaj, Danny Welbeck and Robin van Persie and the latter almost enjoyed a dream return from his knee injury but prodded wide from Jones' delivery.
Fellow striker Hernandez skied over from Evra's 81st minute cutback before Borini came agonisingly close to compounding United's misery, striking the woodwork with De Gea rooted to the spot.
Reports this week suggested Van Persie's countryman Louis van Gaal is the front-runner to become David Moyes' permanent successor at Old Trafford and he may have a major overhaul on his hands on this evidence.