Poland’s Kowalczyk headed to the penultimate event in Falun, Sweden, still with hopes of taking home the crystal globe at the end of the season.
And she couldn’t have done much more, racing to victory in the 10km Classic Mass Start in 32:03.7 minutes.
But despite finishing fourth, in 32:25.4 minutes, Bjoergen did enough to take the overall title, taking her lead to 160 points with just one event left.
Completing the podium in Sweden were the Norwegian duo of Heidi Weng and Therese Johaug, who finished second and third respectively.
Meanwhile, in the men’s 15km Classic Mass Start, Dario Cologna showed no signs of easing off his rivals as he stormed to another World Cup win.
The Swiss Olympic champion headed to Sweden safe in the knowledge that his place atop the overall World Cup standings was safe, having wrapped up the title some time ago.
But the 25-year-old was in no mood to take it easy, crossing the line in 43:14.9 minutes to take victory.
Completing the podium was Norway’s Eldar Roenning who had to settle for second, while Canadian Len Valjas was third.