Longtime major league executive Dan O'Brien Sr. has died at 87.
The Texas Rangers said he died Monday in Dallas.
The Rangers were one of four major league teams with whom O'Brien held front-office jobs over 45 years in professional baseball.
O'Brien was the Rangers' second general manager, from 1973 to 1973.
He began his baseball career in 1955 as a minor league general manager and spent 10 years in the minors before joining the Rangers.
He left Texas to become president and later general manager of the Seattle Mariners. He also worked in the front office with the Cleveland Indians, California Angels, Arizona Fall League and USA Baseball before his retirement in 2000.
His son, Dan O'Brien Jr., was general manager of the Cincinnati Reds during the 2004-05 seasons after working an assistant GM in Texas from 1996 to 2003.