Norway's Johannes Hoesflot Klaebo
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Klaebo profited from the fact that his main rival for the overall title, Russia's Alexander Bolshunov, finished down in seventh.
The 22-year-old was too strong for the rest of the field, holding off home favourite Alex Harvey in a tight finish to secure the victory in 36:10.9 minutes.
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Harvey was just 0.8 seconds behind with Klaebo's compatriot Didrik Toenseth not far behind in third.
Klaebo will take a 52-second advantage over Bolshunov into the individual pursuit on Sunday and that should be more than enough to see him secure his second overall World Cup title in a row.
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