Shadow Fight(1973)

Original title: Бой с тенью

Having failed to enter the institute, Sergei got a job in a workshop to refill lighters. Giving all his free time to his new hobby - boxing, the hero in a short period of time achieves significant success and insists that the coach allowed him to the nearest competition. Having received a well-founded refusal, Sergei goes to another club and wins a victory over a famous boxer at a tournament. But the accidental victory does not bring him joy.