Robertson first started snowboarding at the World Cup level in 2003. His first World Cup podium result came on January 11, 2009, when he won a bronze medal. A month later, he reached the World Cup podium again, this time with a silver medal. He participated in the 2010 Winter Olympics in Vancouver where he won the Silver Medal in the snowboard cross. Robertson was in contention for the gold and was leading at the final corner when he was passed by Seth Wescott. With winning the silver he said that "It was kind of bittersweet. Obviously I wanted to win for sure, but I'm so happy to be second. It's amazing."