Hale, who signed a two-year contract, replaces Joel Skinner, whose contract was not renewed.
A San Jose, Calif., native who attended Campolindo High School in Moraga, Hale previously served under A's manager Bob Melvin as third base and infield coach with the Arizona Diamondbacks from 2007-09. During that time, he played a prominent role on Arizona's 2007 club that posted a 90-72 record and captured the National League West Division championship.
A former Major League player, Hale spent seven seasons as a Minor League manager in the Arizona organization before joining Melvin.
He steered the Triple-A Tucson Sidewinders to the Pacific Coast League and Triple-A titles in 2006 with a franchise-record 91-53 mark. His 220 wins and .542 winning percentage as Tucson's manager from 2004-06 is also a franchise all-time record. He led Rookie-level Missoula to the Pioneer League's best overall mark (44-32) in 2000 and to the Northern Division's second-half championship in 2001. Hale was named the Pioneer League and Baseball America's Rookie-level Manager of the Year in 2001.
Selected in the 17th round of the 1987 draft by Minnesota, Hale spent portions of seven seasons as a player in the big leagues with the Twins (1989-90, 1993-96) and the Los Angeles Dodgers (1997). He was a .277 lifetime hitter with seven home runs and 78 RBIs in 333 games, playing five different positions as well as designated hitter, and registering a .289 (52-for-180) average as a pinch hitter.
While at the University of Arizona (1984-87), he started every game of his collegiate career in setting a record that would not be broken until 2001. Hale established school career marks for most hits and walks, and batted .345 for the 1986 Wildcats team that won the College World Series.
The A's have three coaches in place for next season, as first-base coach Tye Waller and third-base coach Mike Gallego were asked to remain in their roles. Oakland must still fill vacancies for pitching coach, hitting coach and bullpen coach.