 When the war was terminated, he accompanied his wife back to Alsace and quickly joined RC Strasbourg where he played until the end of the decade, reaching the final of the cup in 1947.After the end of his playing career, Mateo continued as a youth coach for RC Strasbourg where he taught the likes of Gilbert Gress, Gérard Hausser, Albert Gemmrich or Léonard Specht.He was responsible for the first team between October 1970 and June 1971 but was not able to save Strasbourg from relegation.