In 2017, Bolshunov took part in the FIS U23 World Ski Championships in the venue Soldier Hollow, Utah, United States, where the 2002 Winter Olympics were held. He won silver in sprint, and a few days later he won the 15 km individual freestyle event. The skiathlon event was marked by a memorable performance by Bolshunov, Alexey Chervotkin and Denis Spitsov, who entered the finish line hand in hand. Bolshunov was declared the winner. As a result, Bolshunov was conferred the highest honorary sports title of Russia, "International Master of Sports".