GOG were on their way to victory, but threw it all away against the French giants Nantes on Wednesday night.
The Danish team had possession and led by two goals as the match entered the final minute, but two turnovers and a missed shot ended up costing them dearly in the first of two Champions League round of 16 matches.
GOG were even ahead by five goals in the second half, but the French miraculously turned it around.
The return match in France will be played in a week, on 8 April, where the two teams will play to meet FC Barcelona in the quarter-finals, where Aalborg has also already secured a place.