Conrado Eugenio (Ramos) Marrero, affectionately known as Connie, played for only 5 seasons in Major League Baseball. It wasn't that he was a poor pitcher, it's just that he was pretty damn old by the time he started his MLB career. Marrero wouldn't throw his first pitch for the Washington Senators until age 38.
Connie enjoyed a long career as a Cuban baseball player prior to coming to the bigs. He wasn't exactly blessed with a natural pitcher's physique, but despite his stature he was incredibly successful in Cuba. Marrero was not exactly a power pitcher either, and relied heavily on slower pitches like curveballs and even knuckleballs. In his 1947-48 Cuban League campaign, he set league records for shutouts in a season (8) and E.R.A. (1.12), and was awarded league MVP honors.
Even though Connie's better days were behind him by the time he began to play ball in the US, he managed a pretty decent 5 seasons with the Senators. He was elected to the American League All-Star team in 1951, and in 1952 he pitched his way to an 11-8 record with a 2.88 E.R.A.