Offseason
- November 27, 2004: Jason Kendall was traded by the Pittsburgh Pirates with cash to the Oakland Athletics for Mark Redman, Arthur Rhodes, and cash.
- December 16, 2004: Tim Hudson was traded by the Oakland Athletics to the Atlanta Braves for Juan Cruz, Dan Meyer, and Charles Thomas.
- December 18, 2004: Dan Haren was traded by the St. Louis Cardinals with Daric Barton and Kiko Calero to the Oakland Athletics for Mark Mulder.
Read more about this topic: 2005 Oakland Athletics Season