 The next Cuban League season, 1947/48, Marrero returned to Almendares in the Cuban League (which was now officially sanctioned by Major League Baseball) and pitched perhaps his best season, going 12–2, setting the Cuban League all-time records for shutouts (eight) and ERA (1.12) and winning the most valuable player award.However, with Almendares tied with the Habana team with one game left, he was unable to clinch the pennant as he lost to Habana's Alex Patterson in a 3–2 game.In 1948/49 Marrero went 6–4, as Almendares easily won another pennant.