Brad Gregory Ziegler (born October 10, 1979, in Pratt, Kansas) is a Major League Baseball relief pitcher for the Oakland Athletics.
Ziegler was drafted by the Oakland Athletics in the 31st round (938th overall) of the 2002 Major League Baseball Draft, but he returned to Missouri State University for his senior year. Upon graduating, the Philadelphia Phillies drafted him in the 20th round (595th overall) of the 2003 Major League Baseball Draft.
He only threw six innings for the short season Batavia Muckdogs due to shoulder tendinitis. The Phillies released him a week before the start of the 2004 season because they felt he was not good enough to pitch in Low-A and too old to return to short season ball. After pitching well in four starts for the Schaumburg Flyers, an independent Northern League team, the Athletics signed Ziegler and he went into the starting rotation for the High-A Modesto Athletics of the California League.