Pitea player Victor Brannstrom had scored after just four minutes against Umedalen in their Division Two North clash when he suddenly sat down and slumped over, according to local newspaper Norrlandska Socialdemokraten.
A kit man and nurse immediately administered CPR to the player until three ambulances arrived and Brannstrom was taken to Pitea hospital, where he was pronounced dead shortly after 4 pm (2pm UK time).
"It is completely incomprehensible. It is so tragic. This is the hardest thing I have experienced," Pitea vice-chariman Christer Berglund said.
Brannstrom, who had previously played for Helsingborgs in Sweden's top flight, had retired from the sport in January following a similar collapse but returned to action when tests indicated he had no serious heart problems.
"That also feels so damn tough but we didn't persuade him to make a comeback - Victor wanted to play himself. He trained and it went well for him," Berglund added.
Pitea hospital said that the player's heart had stopped and that there would be a post-mortem to establish the exact cause of death.