Transactions| Date | Transaction | |||
| 12/23/03 | Designated catcher Michel Hernandez for assignment. | |||
| Kenny Lofton: Signed free agent OF Kenny Lofton to a two-year contract. | ||||
| Tom Gordon: Signed free agent RHP Tom Gordon to a two-year contract. | ||||
| 12/22/03 | Paul Quantrill: Signed free agent RHP Paul Quantrill to a two-year contract with a club option for 2006. | |||
| 12/19/03 | Nontendered OFs David Dellucci and Karim Garcia, making them free agents. | |||
| Miguel Cairo: Signed free agent INF Miguel Cairo to a one-year contract. | ||||
| 12/18/03 | Traded LHP Chris Hammond to the Oakland Athletics for two minor league prospects: RHP Edwardo Sierra and INF J.T. Stotts. | |||
| 12/17/03 | Signed free agent OF Gary Sheffield, who had been with the Braves, to a three-year contract with a club option for 2007. | |||
| 12/15/03 | Selected RHP Joe Orlowski in Rule 5 Draft; lost RHP Colter Bean to Red Sox. | |||
| Signed C John Flaherty to a one-year contract. | ||||
| 12/13/03 | Acquired RHP Kevin Brown from Dodgers for RHP Jeff Weaver, minor league P Yhency Brazoban, a player to be named and $3 million. | |||
| 12/7/03 | Agreed to a one-year deal with OF/DH Ruben Sierra; offered salary arbitration to LHPs Andy Pettitte, David Wells and Gabe White and C John Flaherty | |||
| 12/4/03 | Acquired right-hander Javier Vazquez in a four-player trade with the Montreal Expos for first baseman Nick Johnson, outfielder Juan Rivera and left-hander Randy Choate. | |||
| 12/3/03 | Agreed to a two-year contract with LHP Felix Heredia with a club option for 2006. | |||
| 12/2/03 | Agreed to a one-year contract with INF Enrique Wilson. | |||
| 12/1/03 | Agreed to a one-year contract with 3B Aaron Boone. | |||