Shunsuke Nakamura bent in a superb free kick with nine minutes left to give Celtic a 1-0 win over Manchester United and qualification for the Champions League knockout stages.
Despite dominating for long periods, Alex Ferguson's men were unable to break through Celtic's solid wall of green shirts and the Hoops fans were sent into orbit when Nakamura curled home a magnificent free-kick 10 minutes from time.
United were stunned by the sucker punch but, with seconds remaining, were given the perfect opportunity to level when Spanish referee Manuel Mejuto Gonzalez ruled Shaun Maloney had handled Cristiano Ronaldo's free-kick.
But Louis Saha's nerve failed him when it mattered most and Artur Boruc flung himself to the right to turn away the Frenchman's spot-kick.
The result has booked Celtic a place in the last 16 no matter what happens in Copenhagen in a fortnight's time.
But, for United, following quickly on from their equally unexpected defeat in the Danish capital, the nightmare scenario now looms.
Twelve months ago, they tackled Benfica in the Stadium of Light needing a win to go through and lost.
Two weeks from now, they will entertain the Portuguese giants knowing a similar result will turf them out of the competition at the group stage for the second season running.
Such an outcome could not have been predicted at the start as United, having emerged to a cacophony of noise proceeded to produce a measured, precise passing game that strangled the cries of the Celtic support.
With Ryan Giggs finding room across the pitch, Paul Scholes spraying the ball to all parts and even Rio Ferdinand pushing forward, the Red Devils assumed total control.
All United's performance lacked during those opening 45 minutes was a goal.
They should probably have had at least one, when Scholes floated a crossfield pass into the box which Giggs, having got beyond the Hoops defence, inexplicably failed to control.
Wayne Rooney, without a goal in 12 Champions League games, belted a volley just wide and Giggs turned away in disbelief as his goalbound free-kick flicked off the Celtic wall.
Back-pedalling for long periods in that one-sided opening half, Celtic carved out a single opportunity for themselves, which Thomas Gravesen nodded across goal after being picked out at the far post by Maciej Zurawski.
The Poland international was one of two players withdrawn by Gordon Strachan at half-time as the Celtic boss desperately tried to stem the follow of attacks on the home goal.
Strachan's decision to introduce Jiri Jarosik and Shaun Maloney started to work immediately as Gravesen tested Edwin van der Sar after the Dutch keeper had made a rare mistake.
It took some time for the move to pay off completely though as United's keep-ball exhibition resumed.
The hosts emerged from their bunker long enough for Nakamura to force Van der Sar into his second meaningful save before Ferdinand and Rooney both fired over at the other end, the latter effort coming much closer to breaking the deadlock.
A Ronaldo shot skidded wide off the underneath of Neil Lennon's boot, then Nemanja Vidic headed Giggs' corner wide.
They were only half chances but the missed opportunities were mounting and 10 minutes from time Ferguson saw his side caught by the ultimate sucker punch as Nakamura strode up to curl a magnificent free-kick beyond Van der Sar after Vidic had fouled Jarosik.
United should have levelled immediately when Rooney fed Saha. The Frenchman appeared to be offside. Saha clearly thought so given the relaxed manner in which he tried - and failed - to beat Boruc, turning away aghast when he released the whistle had not blown.
There was one more twist to come. But Saha, who has performed so well this season following the departure of Ruud van Nistelrooy, could not find the finish Ferguson and his team so desperately desired.
