'We had a second half that was far too calamitous to leave us any hope of winning the game against a side who surprised us with their quality,' PSG coach Philippe Bergeroo.

'It looked a bit grim but we recovered very well and we equalised early. It was a super game,' beaming Rosenborg coach Nils Arne Eggen said.

Rosenborg 'showed a side of themselves that warms a soccer heart like mine,' he added.

Paris St Germain, with a clutch of stars including French international striker Nicolas Anelka, went ahead after just seven minutes when striker Christian slotted in.

Christian pounced on the rebound after a shot by Anelka was parried by Rosenborg's Icelandic goalkeeper Arni Gautur Arason, the only non-Norwegian in the team.

The home side, playing in the Champions League for a sixth season in a row, levelled 10 minutes later when Orjan Berg headed the ball past goalkeeper Lionel Letizi, via a post.

The Norwegians gradually got the upper hand and striker Frode Johnsen put them 2-1 up in the 62nd minute, heading in a pass by midfielder Bent Skammelsrud.

Skammelsrud scored in injury time from the penalty spot after Rosenborg's Berg was fouled in the area by defender Sylvain Distin.

The French side mounted a series of threatening attacks but failed to break through the solid Norwegian defence. In the other game in group F, Bayern Munich beat Helsingborg 3-1.

Paris St Germain have been in unpredictable form despite spending more than 450 million French francs ($59.36 million) on transfers during the summer and Anelka faded after looking threatening early in the game.

Among the French team's best chances, Stephane Delmat hit a stinging volley from a corner that was scrambled off the line.