Harmon Clayton Killebrew Jr., June 29, 1936 – May 17, 2011, nicknamed "the Killer" and "Hammerin' Harmon", was an American professional baseball first baseman, third baseman, and left fielder. He spent most of his 22-year career in Major League Baseball (MLB) with the Minnesota Twins. A prolific power hitter, Killebrew had the fifth-most home runs in major league history at the time of his retirement. He was second only to Babe Ruth in American League (AL) home runs, and was the AL career leader in home runs by a right-handed batter. Killebrew was inducted into the National Baseball Hall of Fame in 1984.

Killebrew was 5-foot-11-inch (180 cm) tall and 213 pounds (97 kg). His compact swing generated tremendous power and made him one of the most feared power hitters of the 1960s, when he hit at least 40 home runs per season eight times. In total Killebrew led the league six times in home runs and three times in RBIs, and was named to 13 All-Star teams. In 1965, he played in the World Series with the Twins, who lost to the Los Angeles Dodgers. His finest season was 1969, when he hit 49 home runs, recorded 140 RBIs and won the AL Most Valuable Player Award while helping lead the Twins to the AL West pennant.

With quick hands and exceptional upper body strength, Killebrew was known for both the frequency and distance of his homers. He hit the longest home runs ever recorded at Minnesota's Metropolitan Stadium [520 ft (160 m)], and Baltimore's Memorial Stadium [471 ft (144 m)], and was the first of four players to hit a ball over the left field roof at Detroit's Tiger Stadium. Despite his nicknames and his powerful style of play, Killebrew was a quiet, kind man.

After retiring from baseball, Killebrew became a television broadcaster for several baseball teams from 1976 to 1988. He also served as a hitting instructor for the Oakland Athletics.