Fernando Valenzuela Anguamea (Latin American Spanish pronunciation: [feɾˈnando βalenˈswela]; November 1, 1960 – October 22, 2024), nicknamed "El Toro", was a Mexican professional baseball pitcher. Valenzuela played 17 Major League Baseball (MLB) seasons, from 1980 to 1997 (except for a one-year sabbatical in Mexico in 1992). He played for six MLB teams, most prominently with the Los Angeles Dodgers, who signed him in 1979 and gave him his MLB debut in 1980. Valenzuela batted and threw left-handed, with an unorthodox windup. He was one of a small number of pitchers who regularly threw a screwball in the modern era.

Valenzuela enjoyed his breakout year in 1981, when "Fernandomania" rapidly catapulted him from relative obscurity to stardom. He won his first eight starts, five of them shutouts, and finished with a win–loss record of 13–7 and had a 2.48 earned run average (ERA) in a season that was shortened by a player's strike. He became the first, and as of 2024, only player to win both the Cy Young and Rookie of the Year awards in the same season. The Dodgers won the World Series that year.

Valenzuela peaked from 1981 to 1986, when he was named a National League (NL) All-Star in each season. He won an NL-leading 21 games in 1986, when he was a runner-up to Mike Scott of the Houston Astros for the Cy Young Award. Valenzuela was also one of the better hitting pitchers of his era. He had ten career home runs and was occasionally used by Los Angeles Dodgers manager Tommy Lasorda as a pinch-hitter. In 1986, he signed the then-largest contract for a pitcher in baseball history ($5.5 million/3 years). However, nagging shoulder problems diminished the remainder of his Dodgers career. He was on the Dodgers' 1988 World Series championship team, but sat out the postseason with a shoulder injury. Valenzuela threw a no-hitter in 1990 before the Dodgers released him prior to the 1991 season. He spent the rest of his major league career with the California Angels, Baltimore Orioles, Philadelphia Phillies, San Diego Padres, and St. Louis Cardinals, before pitching a couple of seasons in Mexico in his 40s.

Valenzuela returned to the Dodgers organization after retiring, serving as a broadcaster from 2003 to 2024, the year of his death. The Dodgers retired his No. 34 in 2023. His career highlights include a record of 173–153, with an ERA of 3.54. His 41.5 career wins above replacement (according to Baseball Reference) is the highest of any Mexican-born MLB player.