In 1964, Aragonés was signed by Atlético Madrid where he acquired the nickname "Zapatones", meaning "big boots", since he was known as a free kick specialist. Aragonés picked up silverware in his first season at the club, winning the Copa del Rey (then known as the Copa del Generalísimo). He then helped Atlético to the La Liga title in 1965–66 and again in 1969–70, where he shared the "Pichichi" trophy for the highest scorer in the league with his fellow Atlético forward José Eulogio Gárate and Real Madrid's Amancio. A second Copa followed in 1973 and the team achieved a third league title in 1973–74. The following year, Atlético reached the final of the European Cup played against German champions Bayern Munich. During the match, Aragonés scored a goal late in extra time to give Atlético a 1–0 lead. A 119th-minute equaliser from Georg Schwarzenbeck, however, sent the final to a replay, where Bayern prevailed with a convincing 4–0 victory. His retirement followed soon after and he was appointed Atlético coach for the first time in the same year. To date, Aragonés remains Atlético's all-time top goalscorer and is ninth in the club's all-time appearance list.