Šeller, who competes for the Dukla Liberec , took part in the Slavic Cup for the first time in Horní Mísečky in December 2011 , finishing 44th over 10 km freestyle and 39th place over 10 km classic. At the European Youth Olympic Winter Festival 2013 in Predeal he ran on the 43rd place over 7.5 km classic and on the 24th place in the sprint. At the Nordic Junior World Ski Championships 2014 in Val di Fiemme he came in 36th place over 10 km classic, 31st place in the sprint and tenth place with the relay and at the Nordic Junior World Ski Championships 2015 in Almatyon the 56th place in the skiathlon , on the 12th place in the sprint and on the seventh place with the relay. He made his debut in the World Cup in January 2014 in Nové Město , which he finished in 80th place in the sprint. In February 2016 he finished 62nd place over 15 km freestyle, 35th place over 15 km classic and 31st place in sprint at the U23 World Championships in Râșnov . In the 2016/17 season he achieved seven top ten placements, fourth place in the overall ranking of the Slavic Cup. In Jablonec nad Nisou he achieved his first podium finishes in the Slavic Cup with third place over 3 km freestyle and first place over 10 km classic. At the 2017 U23 World Championships in Soldier Hollow , he finished 21st in the sprint and at the 2018 U23 World Championships in Goms, he took 39th place in the sprint and 34th place over 15 km classic. In February 2019 he finished 55th in the sprint at the Nordic World Ski Championships in Seefeld in Tyrol . In the 2019/20 season, he took his second victory in the Slavic Cup in the sprint in Štrbské Pleso and finished ninth in the overall ranking of the Slavic Cup at the end of the season.
Czech Republic
Štrbské Pleso