Young Russian Alexander Terentev stunned Norwegian superstar Johannes Hoesflot Klaebo to claim his first career World Cup win, in cross-country skiing’s season-opening sprint race in Finland on Friday. Terentev, 22, stormed past world and Olympic sprint champ Klaebo at the last uphill under the floodlights in Ruka en route to success. Klaebo was second and fellow-Norwegian Erik Valnes, last year’s winner at the venue, third in the classic style race in freezing temperatures. “I feel great, I always like skiing in Finland,” said Terentev who has previously won the under-23 and junior world titl…