Hernandez started his career with Atlético Madrid where he made more than 100 competitive appearances, reaching the 2016 UEFA Champions League Final. He also won the 2018 Europa League and the Super Cup in the same year. He signed for Bayern in 2019, winning the Bundesliga, DFB-Pokal and Champions League in his first season as part of a treble. A French international since 2018, Hernandez was part of the winning squad at the 2018 FIFA World Cup and also participated in UEFA Euro 2020.