Marrero was a popular star in his native Cuba, where he had a long and successful career in amateur baseball.

He pitched for Cuba in several Amateur World Series competitions, including the legendary championship game of the 1941 Amateur World Series, and played several excellent seasons with the professional Cuban League and the minor league Havana Cubans.

"[2] Roberto González Echevarría provides the following description: "A bit plump, of less than average height [he was listed as 5 feet 5 inches (1.65 m) tall and 158 pounds (72 kg)], with short arms and small hands, Marrero looked, in uniform, like someone in a baseball costume, not a player.

"[4] At age 102, Marrero was the oldest living former Major League Baseball player at the time of his death.

[5] Marrero was born on a farm called El Laberinto in the district of Sagua la Grande, Cuba; he was of Canarian descent.

Marrero was one of the most popular and successful pitchers in Cuban Amateur League history, winning 123 games from 1938 to 1945.

According to González Echevarría, Marrero as an amateur was considered a bigger drawing card than any professional pitcher in Cuba.

[6] From 1939 to 1943, Cuba hosted the second through sixth Amateur World Series competitions at La Tropical Stadium in Havana.

Only three teams competed and Cuba easily won, with Marrero contributing a victory in the only game he pitched.

Cuba challenged Venezuela to a playoff game, which was scheduled to allow Canónico time to rest.

For the fifth Amateur World Series, the Cuba national team was selected by a fan poll, and Marrero was the top vote-getter.

Although he played only a minor role—pitching in four games and going 1–0—he participated on the winning team of one of the most famous pennant races in Cuban League history.

A week later (now pitching for the minor league Havana Cubans), he suffered a tough 1–0 loss against the Brooklyn Dodgers, allowing four hits and striking out eight.

Cuba swept the series with Marrero contributing a one-run, four-hit, complete-game victory in the only game he pitched.

After being released by Almendares, Marrero signed with the Tigres de Marianao for the 1956–1957 season, where he pitched 19 innings in seven games with a 1.37 ERA.

Baseball Hall of Fame—José Méndez, Ray Brown and Martín Dihigo; the other two are Carlos Royer and Camilo Pascual.)

The Cubans also won the playoffs against the Miami Sun Sox and the Tampa Smokers, with Marrero pitching two shutouts.

During that period, Washington's roster also included a number of other Cuban players, such as pitchers Sandy Consuegra and Camilo Pascual and catcher Mike Guerra.

The Senators were a second division team, never finishing higher than fifth place in the eight-team league while Marrero pitched for them.

Marrero is a respected figure in Cuba; his portrait is shown on a mural at Estadio Latinoamericano, and he threw out the first pitch at the 1984 baseball World Championship.

[24] In 2006, Marrero was featured along with his Almendares teammate, Hall of Famer Monte Irvin, in a documentary about Cuba's baseball, "The Bases Are Loaded.

"[25] He did not draw a major league pension and was reported to be living modestly in a room in a relative's Havana apartment.

[26] As recently as early 2007, a baseball tour of Cuba advertised that participants would have an opportunity to visit with the 95-year-old Marrero.

[27] On April 25, 2013, Marrero celebrated his 102nd birthday with family and friends, "an unlit Cuban cigar in his mouth and a baseball cap on his head."

Earlier in the year, he received a $20,000 payout from Major League Baseball, a payment granted to those who had played between 1947 and 1979, which had been held up due to issues surrounding the United States's embargo on Cuba.