During his career, Juan Carlos played for Real Valladolid (two spells, to kickstart and end his 15-year spell as a professional), Atlético Madrid, FC Barcelona and Valencia CF. With "Barça", he started and finished in the club's 1991–92 European Cup final win against U.C. Sampdoria, and was relatively used in three consecutive La Liga titles by the Catalans. He played 297 league games as a professional, all in the top level, scoring two goals – both for Valladolid.