Dan O’Brien Sr. was born in 1929, and died on January 16, 2017.
He was a front office executive in Major League and minor league baseball.
O’Brien Sr was the father of Dan O’Brien Jr., a former MLB general manager, and scouting director.
He came to the major leagues after nine years (1964–72) as assistant to Philip Piton and Hank Peters, presidents at the time of the National Association of Professional Baseball Leagues, the minor leagues’ governing body.
O’Brien Sr joined the Texas Rangers as a vice president during the 1973 season, and was promoted to general manager of the Rangers later that season; he would continue in that post through 1978, although he shared power with co-general manager Eddie Robinson in 1977–78.
During 1979, he became president of the Seattle Mariners, then in their third year as an American League expansion team, and he added the general manager title to his duties from 1981–83, replacing Lou Gorman.
O’Brien Sr left Seattle in 1984 and joined the front office of the Cleveland Indians in 1986, working with Peters again as his top assistant in 1987–89.
He then moved to the California Angels as top aide to general manager Mike Port and then succeeded Port as the team’s GM from the close of the 1991 season through 1993.
O’Brien Sr was replaced by Whitey Herzog at the end of the ’93 campaign Of O’Brien’s three major league teams, only the Rangers of the late 1970s experienced sustained success, contending for, but never winning, the championship of the American League West Division.
However, the Mariners climbed to the middle of the pack in the AL West in 1982, then fell into the basement, with 102 losses, in O’Brien’s last year.
In Anaheim, he inherited a .500 team, but the Angels lost 90 games in 1992 and 91 games more in 1993.
He died in Dallas.
Dan O’Brien Sr. passed away at 78 years old.