Overall World Cup leader Petter Northug of Norway reinforced his lead in the event
Rickardsson claimed his first World Cup podium when he dominated Lukas Bauer in the men's 10km classic, the Czech finishing 1.7s behind with Northug in third at 6.2s.
Northug has already won three stages of the Tour de Ski, which finishes this Sunday and currently leads Sweden's Marcus Hellner by 20.1sec in the event standings.
Inspired by the Four Hills ski jumping tournament and the Tour de France bike race, the Tour de Ski comprises a prologue and seven stages over 10 days, linking Germany and Italy via the Czech Republic.
Stage winners add 50 points to their overall World Cup tally, as opposed to the 100 points offered for traditional World Cup wins. The winner of the Tour de Ski adds 400 points to his overall World Cup tally.
The event ends this Sunday in Val di Fiemme, Italy.