Crnković started biathlon for the first time in February 2012 at the Junior World Championships in Kontiolahti and finished 84th in the sprint, 75th in the individual and 20th in the relay. His best results at the Junior World Championships 2013 in Obertilliach were 50th place in the sprint and 19th place with the relay. In December 2014, he ran his first World Cup race in Hochfilzen , which he finished in 103rd place in the sprint. At the 2016 Biathlon World Championships in Oslo , he came 83rd in the sprint and at the Biathlon World Championships 2017 in Hochfilzen, he came 96th in the individual and 83rd in the sprint. In January 2017 he got his first World Cup points in Oberhof with 37th place in the sprint with two shooting errors.