Aged 27, Reina left "Barça" and signed for Atlético Madrid, rarely missing a game in his first five seasons and winning the 1977 national championship – his only in the competition. He also reached the final of the 1974 European Cup against FC Bayern Munich at the Heysel Stadium in Belgium: after 90 minutes the match was tied 0–0 and, in the 114th minute, Luis Aragonés scored for the "Colchoneros", but Reina let in a long-range shot with just seconds to go and the Spaniards went on to lose the replay 0–4.