Emil Iversen held off compatriot Sjur Roethe in a dramatic finish as Norway swept the podium places in the 30km skiathlon in Lahti, Finland.
Iverson, here winning his eighth individual biathlon World Cup race, launched a blistering attack late on in the downhill section heading into the stadium while rival Hans Christer Holund suffered a race-defining crash.
Holund took over the lead at the halfway stage from Roethe but, in the closing stages, could not live with Iversen's advances and crashed, also touching overall standings leader Alexander Bolshunov in the process.
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That left Iversen to win in a time of 1:10:18.4 minutes, 0.4 seconds clear of Roethe and 6.6s ahead of Paal Golberg in third.
Bolshunov recovered to finish fifth with Holund one place further back, and he continues to head the overall standings on 1,391 points - a mammoth 731 clear of Ivan Yakimushkin in second.
The action stays in Finland with a relay on Sunday.
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