Isidro Márquez Espinoza (born May 14, 1965) is a Mexican former professional baseball pitcher. He played in Major League Baseball (MLB) for the Chicago White Sox.
Career
Márquez played during one season at the major league level for the Chicago White Sox. He was purchased by the Los Angeles Dodgers from the Mexican League's Tuneros de San Luis in 1988. Márquez played his first professional season (in American baseball) with their Class A-Advanced Bakersfield Dodgers in 1988, and his last affiliated season with the White Sox and their Triple-A Nashville Sounds in 1995.
In 2000, he made a comeback with the Piratas de Campeche of the Mexican League. He pitched in Mexico through 2011.
In 2020, Márquez was inducted into the Mexican Professional Baseball Hall of Fame.
In 2021, the Piratas retired Márquez's 33 number. On 30 October 2022, the Águilas de Mexicali also retired Márquez's 33 number.
In February 2025, Márquez was selected by a committee of journalists as a pitcher for the Mexican League Centennial All-Time Team on the occasion of the league's hundredth anniversary.