CAVALESE, Italy (AP) — Three-time champion Dario Cologna of Switzerland surged into the Tour de Ski lead after Saturday's penultimate stage as previous leader Petter Northug Jr. of Norway struggled in the 15-kilometer classical mass start race.
Alexey Poltoranin of Kazakhstan won the sixth leg in a sprint finish, clocking 39 minutes, 1.5 seconds to finish just 0.01 ahead of Len Valjas of Canada. Another Canadian, Alex Harvey, crossed third, 0.4 back.
Cologna finished 11th, 10.7 behind, while Northug was only 28th, 29.3 back. Cologna now holds a 6.5-second lead over Alexander Legkov of Russia, who was 17th on the day, with Northug 11.5 back heading into Sunday's final stage, the traditional climb up Mount Cermis.
Legkov would have been in the lead but he was penalized 15 seconds for obstructing a competitor. It was an emotional day for Legkov, as six Russians were killed and two others seriously injured in a snowmobile accident on a nearby ski slope Friday night. Most of them were tourists.
Earlier, three-time defending champion Justyna Kowalczyk of Poland dominated the women's 10K event for her fourth stage victory in this year's race, extending her overall lead. Kowalczyk clocked 28:12.9 to finish 33.2 ahead of Norway's Kristin Stoermer Steira and 38.5 in front of Finland's Krista Lahteenmaki.
In the overall standings, Kowalczyk now has a 2:08 lead ahead of Norway's Therese Johaug, with Steira 2:17 back in third. The tour ends Sunday with the traditional climb up Mount Cermis in Val di Fiemme, which will also host this season's world championships from Feb. 20-March 3. Both men and women have 9K freestyle races with handicap starts.