Leonard Eugene Alley (born July 10, 1940) is an American former professional baseball player. He spent his entire career in Major League Baseball as a shortstop for the Pittsburgh Pirates from through . A two-time All-Star who was widely acclaimed to be the best all-around shortstop in the majors for two seasons (1966-67) before a recurring right shoulder problem reduced his effectiveness, Alley was a member of Pirates teams that won three consecutive National League Eastern Division titles between and and the World Series in .
A contact hitter with occasional power, Alley handled the bat well. He was an excellent bunter and adept at the hit-and-run maneuver. In the field, he had plus range and quickness as well as an accurate throwing arm. He attended Hermitage High School in Henrico, Virginia. Because of a recurring problem with his throwing arm, he did not play shortstop for the next three years. He was a frequent backup to starting shortstop Ducky Schofield.
1966 was his first full year at shortstop. He had a .979 fielding percentage (second in the league behind Chico Cardénas' .980), and led all National League shortstops in turning double plays with 128. He received the Gold Glove Award for NL shortstops. In the same year, Mazeroski set the all-time double play record for second basemen in a season with 161. The Pirates as a team turned 215 double plays, the second most in baseball history after the record 217 set by the 1949 Philadelphia Athletics (as of 2023). Alley also hit for a career high .299 batting average, had a career high with 88 runs scored,
In 1967, Alley led the league's shortstops again in double plays with 105, as well as leading the league's shortstops in putouts (257) and was second in assists (500). He again won the Gold Glove Award. He batted .287, and had a career high 55 RBIs. From 1965 to 1968 he was in the top four NL players in assists. and 1967, along with their teammate Roberto Clemente. They also joined a select list of eight shortstop-second baseman duos to each win a Gold Glove the same season more than once while playing together.
Alley was on Pirates teams that won their division in 1970 through 1972, and had the NL's best record in 1971 and 1972. They lost in the NL championship series to the Cincinnati Reds twice (1970, 1972), but defeated the San Francisco Giants in 1971, and went on to win the World Series against the Baltimore Orioles (Alley only appearing in one playoff game and two games of the World Series, having suffered a knee injury). In 2013, he received the Paul Keyes RBI (Richmond Baseball Impact) Award, given annually to a person making a significant contribution to baseball within or around the Richmond community.