The creations corresponding to the 1940s held in the Museum were executed in Puerto Rico. During this period, Esteban – who had become an American citizen in 1942 – shows a certain New York influence but without abandoning his European personality.
They are academeic drawings of familiar scenes in which the artist reveals a cubist influence.
During the 1950s, the collage technique becomes very relevant to his work as a result of the influence of synthetic cubism, introducing certain characteristics of gestural painting and the continuity and contrast given by the intertwining of the forms. At the same time, during this period the painter took part, together with a group of New York artists, in the resurgence of a new artistic language, a kind of abstract action, gestural and aggressive painting which, in the case of Esteban, became more lyrical and was created using different flat areas with free and regular lines but with an ordered composition.