| Date | Transaction | |||
| 10/29/04 | Signed LHP Jamie Walker to a one-year contract with a club option for 2006; Signed RHP Craig Dingman and RHP John Ennis to minor-league contracts with invitations to Spring Training. | |||
| Declined the club option on RHP Al Levine, making him a free agent. | ||||
| 10/25/04 | Outrighted LHP Rob Henkel to Triple-A Toledo. | |||
| 10/24/04 | Signed RHP Justin Verlander to a five-year contract. | |||
| 10/15/04 | Claimed OF Byron Gettis off waivers from the Royals and claimed OF Dewayne Wise off waivers from the Braves. | |||
| 10/8/04 | Claimed RHP Colby Lewis off waivers from the Rangers. | |||
| 10/6/04 | Outrighted RHP John Ennis and RHP Craig Dingman to Triple-A Toledo. | |||
| 10/1/04 | Claimed OF Alexis Gomez off waivers from the Kansas City Royals. | |||
