Dennis O'Brien played most of the 1970s on NHL defenses, totalling nearly 600 games. Best known as a Minnesota North Star he also played briefly in Cleveland, Colorado and Boston.
A big, tough, stay-at-home defender (he only scored 27 goals and 122 points), he is the answer to a neat trivia question. In 1977-78 he became the first player for four NHL teams all in the same season!
By the way, Dennis is the uncle of Shane O'Brien.