José DeLeón, a right-handed pitcher, made his debut in Major League Baseball with the Pittsburgh Pirates. Born on December 20, 1960, in La Vega, Dominican Republic, DeLeón's journey to the major leagues began when he signed with the Pirates as an amateur free agent in 1979. His early years in the minor leagues showcased his potential, and by 1983, he was ready to step onto the major league stage.

DeLeón's rookie season with the Pirates was marked by a promising start. He quickly became known for his powerful fastball and ability to strike out batters. In his debut season, he recorded an impressive 2.83 ERA over 15 starts, signaling his potential as a future ace. However, consistency would prove to be a challenge throughout his career.

In 1986, DeLeón was traded to the Chicago White Sox, where he continued to demonstrate his pitching prowess. During his time with the White Sox, he led the American League in strikeouts in 1989, amassing a total of 201. Despite his ability to rack up strikeouts, DeLeón often struggled with control, leading to a higher number of walks and fluctuating performance.

The St. Louis Cardinals acquired DeLeón in 1988, and he spent several seasons with the team. His tenure with the Cardinals was highlighted by a strong 1989 season, where he posted a 3.05 ERA and struck out 201 batters, tying his career-high. This performance earned him recognition as one of the league's top strikeout pitchers, although his win-loss record did not always reflect his skill due to limited run support.

DeLeón's career continued with the Philadelphia Phillies, where he played from 1992 to 1993. His time with the Phillies was marked by injuries and inconsistency, which limited his effectiveness on the mound. Despite these challenges, he remained a valuable asset to the team's pitching rotation when healthy.

In the latter part of his career, DeLeón joined the Montreal Expos. His stint with the Expos was brief, and he retired from professional baseball after the 1995 season. Over his career, DeLeón accumulated a total of 1,594 strikeouts, demonstrating his ability to overpower hitters with his fastball.

José DeLeón's career was characterized by his impressive strikeout ability and moments of brilliance on the mound.