A photograph of the daring pair, who remain unidentified, has gone viral on the internet.
The two fans were spotted under floodlights in the pitch's centre circle by security staff at Broendby's Copenhagen ground, following a scoreless match against rival Randers on Sunday.
Subsequently, a picture of the fans was posted on Twitter.
"I do not know who posted the pic," Broendby IF spokesman Mikkel Davidsen told AFP.
"Great match, but disappointed over the 0-0 and many missed chances. But the couple ...in the centre circle helps the mood," Davidsen wrote on Twitter.
"We have several eye witnesses," he added.
After they were spotted, the pair were told to put their clothes back on and leave the stadium.
Broendby are currently at the bottom of the Danish Superliga championship tournament.