1949-50 Acebo card of Conrado Marrero. Note that blank backs are a recognized variation, and also note visible pen marks.The 1949–50 Acebo issue is a scarce and highly regarded Cuban baseball set from the postwar golden era of winter league collecting. This example features Cuban pitching legend Conrado Marrero, one of the most dominant and celebrated arms in Cuban baseball history. Marrero starred for the Alacranes de Almendares in the Cuban Winter League, where his control, deception, and remarkable longevity made him a perennial standout against elite competition. He later extended his legacy in Major League Baseball with the Washington Senators, where he became one of the most successful Cuban pitchers of his era and a pioneering figure for future generations of Latin American players.