In September 2018 it was announced that he would join Team Sunweb from 2019 on a three-year contract, having been a member of Development Team Sunweb in 2018.[4][5] In the same month, Hirschi won the under-23 road race at the UCI Road World Championships in Innsbruck, Austria.[6] In August 2020, he was named in the startlist for the 2020 Tour de France,[7] during which he won a stage, three combative rider awards for his performances on individual stages and the overall Combativity award. One week after the end of the Tour, he took the bronze medal in the Men's road race at the Road World Championships in Imola.[8] Three days later Hirschi took the win at La Flèche Wallonne, pulling away from the rest of the lead group in the last 50 metres of the final climb of the Mur de Huy. He was the first Swiss rider to win the race since Ferdinand Kübler in 1952.[9][10]
In January 2021, Hirschi's contract with Team DSM was terminated by mutual consent,[11] and he signed a three-year contract with UAE Team Emirates.[3]