Rene Zahkna started in the IBU Cup for the first time in 2011 . At the Junior World Championships in the next season, he ran twice on the podium. In the sprint race he was third and in the pursuit that followed he was able to improve to second place. The next year he took part in the junior races of the European Championships and won the individual race and was, together with Meril Beilmann , Tuuli Tomingas and Johan Talihärm , third in the mixed relay race. At the end of this season, Zahkna took part in races of the Biathlon World Cup for the first time and finished 67th in the sprint in Kontiolahti . At the European Championships in 2015 , he won silver in the juniors both in singles and in pursuit. He has been taking part in World Cup races regularly since the 2015/16 season and achieved his first World Cup points in 2016 with a 34th place in the individual. He finished the season with a 97th place overall. In the following season , Zahkna could not achieve any World Cup points. His best individual result was a 45th place in the individual at the World Championships in Hochfilzen . At these world championships he reached 21st place with both the mixed relay and the relay.
In the 2017/18 season he again won World Cup points with a 34th place at the World Cup opener in Östersund . But these points were the only ones this season. He finished the season with a 90th place overall. At the European Championships in Ridnaun , he narrowly missed the podium with a fourth place in the single mixed relay, together with Regina Oja . In the sprint, he reached 76th place.
At the 2018 Winter Olympics in Pyeongchang Zahkna participated. In the sprint he was 75th, in the individual 65th and with the relay he reached 13th place.
Estonia
| Pyeongchang
Kontiolahti
Oslo
Hochfilzen
Ridanna
Presque Isle
Minsk