In his first senior season he earned a bronze medal at the 2011 Heidenheim World Cup and a silver medal at the 2015 Vancouver World Cup. These results caused him to be selected for the 2011 European Championships in Sheffield. In the individual event Gustin defeated Hungary's Géza Imre and Switzerland's Benjamin Steffen, but fell to Max Heinzer, also from Switzerland, in the table of 16. In the team event France overcame successively Switzerland, Ukraine and Hungary to win the gold medal.