Having met in 1968, the couple joined vocal group Mocedades, with whom they recorded three albums before leaving in 1972 to concentrate on a career as a duo.
At the 20th Eurovision Song Contest, held in Stockholm on 22 March, "Tú volverás" placed 10th of the 19 entries.
The couple had married in 1975, and took a career break in the early 1980s during which Estíbaliz gave birth to a daughter.
Returning in 1983, they again began releasing albums on a regular basis, with 1985's Cuidado con la noche proving the most successful of their career.
[3] Sergio Blanco died on 15 February 2015 in Tres Cantos, Community of Madrid, at the age of 66.