Historically speaking, one of the most important Pitchers in Latin America is Dennis Martinez, and he was also among the longest-tenured.

Martinez broke in with the Baltimore Orioles in 1976, and he became the first player from Nicaragua to make the Majors.  The righthander did well, earning a place in the starting rotation and had five 14-win seasons for the O's, including a league-leading 14 in the strike-shortened 1981 season.  Martinez finished fifth in Cy Young voting that year, but he had an awful 1983 season, with an ERA well over 5.  He was left off of the postseason roster, and the Orioles won the World Series. Martinez continued to struggle, and it was learned that he was a heavy drinker, and alcoholism threatened to end his career early.

The Nicaraguan got clean, but he didn't have time to focus on both pitching and sobriety, and a change of scenery in the form of a 1986 trade to Montreal was just the tonic he needed.  With the Expos, Martinez went to three All-Star Games, won the ERA Title in 1991 (2.39), and had five top-ten finishes in bWAR for Pitchers.  

At age 40, Martinez signed with the Cleveland Indians to have another All-Star year amongst the three he played in Ohio.  He carved out two more years, one with Seattle and one with Atlanta, and Martinez retired with 245 Wins, which at the time placed him first among all Hispanic Pitchers,

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Eddie Rommel played his entire 13-year playing career with the Philadelphia Athletics (1920-32), where he became one of the first masters of the knuckleball.

Rudy York was known mostly for his time with the Detroit Tigers, and it was there where he had his greatest success.

Prior to winning the World Series MVP in 1972, you could argue that Gene Tenace was one of its most unlikely recipients.  The Catcher made his first appearance in the Majors in 1969 for Oakland, but he was mostly a backup.  Late in the ’72 season, Tenace was promoted to a starter, and he belted four Home Runs in World Series.