Johannes Høsflot Klaebo and Ingvild Flugstad Østberg each have one hand on the International Ski Federation Tour de Ski trophies after mass start wins on the penultimate stage in Val di Fiemme.
The two Norwegians lead the men's and women's standings respectively, both by useful margins, with just the nine kilometre climb races to go in the Italian resort tomorrow.
Triple Olympic champion Klaebo also won the last stage in Oberstdorf on Thursday (January 3) and has won four of the six stages so far.
He triumphed today by finishing the 15 kilometre course in 40min 52.6sec, meaning he now leads overall by one minute and 20 seconds.
Second overall is Russia's Sergey Ustiugov, although he has dropped further behind Klaebo after only finishing 16th today in 41:34.6.
Coming second in today's race was Italy's Francesco De Fabiani in 40:53.2, just 0.6 seconds behind Klaebo.
He now sits fourth overall, while another Russian Alexander Bolshunov came third in today's event.
He crossed the line in 40:55.2 and sits third overall.
Though Klaebo’s Tour win is not officially confirmed with today's victory, such is the extent of his lead it is highly unlikely he will lose the title in tomorrow's short climb.
Østberg meanwhile is in the same situation on the women's side thanks to her victory today.
She triumphed in 29:34.4 on their 10km course finishing 10 seconds ahead of Russia’s Natalia Nepryaeva, while another Russian, Anastasia Sedova, finished third in 29:45.2.
It means Østberg has also now won four stages, with all her wins coming in succession.
With just tomorrow's race to go she leads Neprayaeva in the overall standings by 53.4 seconds, with a cumulative time of 1:55:16.2.
Finland hold third overall through Krista Parmakoski, who came fourth today in 29:46.9.
Tomorrow’s final stage will start at 1pm local time for the women and 2.45pm for the men.