Rochat learned to ski at the age of two in Crans-Montana , four years later he competed in the first children's races. As a 15-year-old he took part in FIS races for the first time in January 2008 , but his development was interrupted several times by serious knee injuries in the following years. He had to be operated on six times in total, which is why he initially focused on a successful Matura . For these reasons, he missed most of the 2011/12 season and the entire 2013/14 season, which is why he was never able to take part in the Junior World Championships.
In the European Cup Rochat was the first time in December 2012 at the start and was classified a month later for the first time in the points. In spring 2015 he won three FIS races, which enabled him to join the Swiss-Ski squad . He made his World Cup debut on December 13, 2015 in Val-d'Isère , where he was eliminated. At his second World Cup race on January 6, 2016 in Santa Caterina , he achieved 27th place with the high starting number 62 and thus scored his first World Cup points. In the further course of the season, however, he was unable to qualify for a second round.
In the winter of 2016/17 Rochat finished second in the European Cup slalom twice, while he made it into the points twice in the World Cup. On December 6, 2017, he won a European Cup slalom for the first time. Because of numerous failures, he could not qualify for the Olympic Games in Pyeongchang. At the first post-Olympic slalom on March 4, 2018 in Kranjska Gora , he finished 6th and achieved his best career result to date.
Switzerland