Career
Hellner had a total of seven victories in the junior levels of cross-country skiing up to 30 km from 2003 to 2005. At the 4 × 10 km classic/free, Hellner took gold for Sweden after leading the race from the very start. In the 2011 FIS Nordic World Ski Championships in Oslo, Hellner opened his championship with winning a victory in the men"s sprint.
A couple of days later, Hellner, like in the 2010 Winter Olympics, rode the last lap for Sweden in the 4 × 10 km relay.
This time finishing second, winning a silver medal for Sweden. In the 2012, Hellner became the first Swedish male skier to be on the podium in Tour de Ski by securing a second place overall after passing Petter Northug in the final uphill event.
Hellner participated in the 2010 World Series of Poker main event. In March 2012, Hellner joined Team Pokerstars SportsStars alongside Mats Sundin and Boris Becker.