Martinez entered the Paris École des Beaux Arts, Atelier Gérome in 1897. In 1898 he sent a number of paintings of Paris scenes back to the Bohemian Club for an exhibition in San Francisco. He enjoyed the company of Henri Matisse and graduated from the École in 1899. In 1900 he entered the Academy of Eugène Carrière and his "Portrait of Miss Marion Holden" – a Tonalist work similar to "Whistler's Mother" – won an honorable mention in the Mexican display at the Paris International Exposition.