The student has been taking part in snowboard competitions since 1998, but it wasn't until 2003, when he was able to join the junior squad of the Norwegian national snowboard team in addition to participating in the first international competition, that he achieved his breakthrough. A year later, however, some snowboarders had to leave the junior team due to the poor economic situation, including Sivertzen.
At the end of the 2006/07 season , after good results in his first FIS races , Sivertzen made the leap into the senior team, for which he competed in the 2007 World Championships and in three World Cup races in his specialty snowboard cross . While he did not get past 31st place in the World Cup, he already reached fifth place in his third World Cup. In April 2007 Sivertzen was also junior world champion and after the season was named Rookie of the year .
Also in the 2007/08 season Sivertzen took part in the World Cup and won the first World Cup race in the Valle Nevado . Just three days later, he repeated his podium finish there and finished second. Overall, with one World Cup victory and two second places, he achieved second place in snowboard cross and eighth overall World Cup that season. However, he could not defend his junior world championship title in ninth place.
Norway
World cup
