The 22-year-old came into the final race of the season in a good position after a fantastic victory in the Mass Start on Saturday.
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He began with a gap of more than 50 seconds between himself and Bolshunov, who had to win to have any chance of snatching the title.
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However, Klaebo skied strongly, despite Bolshunov closing the gap, and he held off the Russian and local hero Alex Harvey in a dramatic finish.

Klaebo holds off Bolshunov to secure title

Victory seals a World Cup Final hat-trick for Klaebo and he defends his overall Crystal Globe from last season.
The Norwegian finished with a time of 29:05.4, 2.8 ahead of Harvey and 2.9 in front of Bolshunov.
His success caps a wonderful double for Norway after Ingvild Flugstad Oestberg won the women’s Crystal Globe earlier on Sunday.
After a silver on Saturday fan favourite Harvey bade farewell to his career with another second-placed finish to cap a fine end to his time on the tour.
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