During the 1950s he collaborated on the review Asir. In 1955 he published his first book, Tata Vizcacha, a satire of various personalities in his native city. After that he devoted himself heavily to poetry, eventually earning himself a place among the most important Uruguayan poets of his generation.
During the dictatorship of Juan María Bordaberry, he promoted the revolutionary possibilities of popular music
Benavides taught literature at the secondary level He later joined the Faculty of Humanities and Educational Sciences in the Department of Modern and Contemporary Letters of the University of the Republic, Uruguay.
He has also worked in radio broadcasting. His poems have been set to music by Daniel Viglietti, Alfredo Zitarrosa, and Héctor Numa Moraes.
Examples include "Como un jazmín del país", "Milonga del Cordobés", "Yo no soy de por aquí", and "Tanta vida en cuatro versos".