Manchester United were held to a draw by Aalborg at Old Trafford - but still topped their Champions League group.
Carlos Tevez gave United the lead after three minutes when he slid in a perfect pass from Ryan Giggs.
But Aalborg equalised when Michael Jakobsen headed home after 31 minutes and Jeppe Curth's header on the stroke of half-time gave Aalborg a shock lead.
Wayne Rooney's powerful finish put United level after 52 minutes, but Aalborg held on bravely for a point.
It was a below-par show from Sir Alex Ferguson's reigning champions, but United's main goal was achieved as they finished at the head of Group E in readiness for the draw for the last 16 next week.
But once again Rooney's temperament was questioned after a number of clashes with his Danish opponents.
Aalborg's caretaker coach Allan Kuhn celebrated at the final whistle, as he was entitled to do after a performance of huge courage from his players.
With qualification for the knockout phase already assured, Ferguson was also able to rest some of his influential stars ahead of a crucial Premier League game at Spurs on Saturday.
Cristiano Ronaldo was sidelined by injury, but he received his Ballon d'Or European Footballer of the Year trophy on the pitch prior to kick-off, standing alongside Denis Law and Sir Bobby Charlton, who won the award in 1964 and 1966 respectively.
With the formalities over, United's reshaped side made a perfect start early on to score the quickest Champions League goal this season.
Giggs was the creator with a precise through pass, giving Tevez the simplest of chances to slip a cool finish beyond Aalborg keeper Karim Zaza.
Tevez then missed an easier chance to double United's lead two minutes later, when he side-footed wide with the goal at his mercy after being set up by Rooney.
United dominated the opening exchanges with almost embarrassing ease, but paid for their wastefulness in front of goal when the visitors equalised after 31 minutes.
Jakobsen escaped the attentions of United's defenders in the area to direct Due's free-kick beyond Tomasz Kuszczak, who got a hand to his header and should have done better.
Remarkably, Aalborg then took the lead in the closing seconds of the first half when Due picked out Curth, who directed a clever header into the far corner beyond the stranded Kuszczak.
United made a double change at half-time, sending on Paul Scholes and Ji-Sung Park for Giggs and Darron Gibson.
And they restored equality seven minutes after the break when Rooney steered in a low drive as he raced on to Anderson's pass.
Rooney, who had been involved in some needless spats with Aalborg defenders, almost set up a rare goal for Gary Neville with 19 minutes left.
The veteran defender arrived unmarked at the far post, but his shot was blocked by Zaza.
And Rooney was frustrated again seconds later when his cross into the box was headed on to his own bar by Aalborg defender Steve Olfers.
Rooney was at the centre of all United's best work, creating an opening for Tevez with only six minutes left.
The Argentine rounded Zaza, but the angle was too tight and he could only find the side-netting.
The draw enabled United to equal the record 19-match unbeaten run in Europe's top competition, also held by Ajax and Bayern Munich, and they can now set their sights on the knockout phase and a repeat of last season's triumph in Moscow.
Man Utd: Kuszczak, Neville (Rafael Da Silva 76), Ferdinand, Evans, O'Shea, Nani, Gibson (Park 46), Anderson, Giggs (Scholes 46), Rooney, Tevez.
Subs Not Used: Foster, Vidic, Fletcher, Possebon.
Goals: Tevez 3, Rooney 52.
AaB: Zaza, Bogelund, Olfers, Jakobsen, Pedersen (Sorensen 76), Curth (Caca 74), Enevoldsen, Augustinussen, Risgaard, Due (Kristensen 65), Saganowski.
Subs Not Used: Kenneth Nielsen, Nomvethe, Braemer, Ronnie Schwartz Nielsen.
Goals: Jakobsen 32, Curth 45.
Ref: Laurent Duhamel (France).
BBC Sport Player Rater man of the match: Manchester United;s Carlos Tevez 7.60 (on 90 minutes).
Please note that you can still give the players marks out of 10 on BBC Sport's Player Rater after the match has finished.
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