Celtic 1 Aberdeen 2
Celtic's hopes of going through the Premier League campaign unbeaten were crushed by an unexpected home defeat at the hands of Aberdeen last night.
Dons manager Steve Paterson confessed before kick-off that all he was hoping for was a defeat that was not too painful for his injury-ravaged side, which featured nine players under 21.
But when substitute Bryan Prunty, the former Celtic reserve, cancelled out Henrik Larsson's 15th-minute opener the stage was set for an upset no one had been predicting.
Aberdeen rode their luck and won it at the death with a fine break that saw Australia international David Zdrilic slot past David Marshall.
It was the first time Celtic had been beaten in front of their own fans in 77 games - when Ajax had won a Champions League qualifier in August 2001.
Celtic attacked regularly against nervous opponents and so jittery were the visitors that Larsson's 15th-minute goal had seemed a long time coming.
Momo Sylla set it up with a flick high over the Dons' defence and the Swede had no difficulty slotting past David Preece for his 36th goal of the season and the champions' 99th in the campaign.
Celtic made a change at the break with Jamie Smith coming on for Didier Agathe and within five minutes Jackie McNamara had limped off to be replaced by Bobo Balde. And Celtic were content to meander along happily until Prunty shocked them with a 56th-minute equaliser.
The impressive Scott Muirhead was the man who made it happen with a low ball in from the left that neither Marshall nor a defender could reach and there was Prunty at the back post to apply a close-range finish.
Martin O'Neill made a final change in the 67th minute when he sent Liam Miller on for Stephen McManus in the hope of getting some extra creative spark.
But the Dons had the final say and Zdrilic got the better of Paul Lambert in a race for a long ball before slotting past Marshall.
CELTIC: Marshall; McNamara (Balde 49), Varga, McManus (Miller 67), Agathe (Smith 45), Lennon, Lambert, Petrov, Wallace, Larsson, Sylla. Subs not used: McGovern, Beattie. Goal: Larsson 16.
ABERDEEN: Preece; Higgins, Rutkiewicz, Muirhead, Morrison, Tosh (Prunty 23), Heikkinen, Sheerin, Buckley, Zdrilic, Foster. Subs not used: Esson, Souter, Stewart, Donald. Booked: Sheerin. Goals: Prunty 56, Zdrilic 90.
Referee: I Brines (Scotland).