On 3 July 2019, Atlético Madrid announced via their website that they had reached an agreement with Herrera. He signed a three-year contract, and was officially presented at the Wanda Metropolitano with the number 16 shirt. After failing to appear for "Los Rojiblancos" in the first month of the season, he made his competitive debut on 18 September, coming on as a late substitute for Thomas Partey and scoring the equalizer in the 90th minute to salvage a 2–2 draw against Juventus in the opening group game of the UEFA Champions League. Three days later, Herrera made his debut in La Liga as a starter against Celta de Vigo, playing 60 minutes in a 0–0 draw. He was a starter in both Supercopa de España matches against Barcelona and Real Madrid, finishing runner-up against the latter in the final. He made 30 appearances across all competitions in his debut season with Atlético, though his playing time was mostly hampered due to numerous injuries.