| MLB Transactions |
| March 15, 2010 |
| ARZ - Kris Benson: Signed to a Minor League Contract |
| ARZ - Mark Reynolds: Signed, ( 2010-2012; Opt 2013)(three-year extension) |
| ATL - James Parr: Sent to Minors |
| BAL - Troy Patton: Sent to Minors |
| FLA - Sean West: Sent to Minors |
| LAD - Scott Elbert: Sent to Minors |
| NYM - Josh Thole: Sent to Minors |
| OAK - Clayton Mortensen: Sent to Minors |
| PIT - Donnie Veal: Sent to Minors |
| SD - Aaron Poreda: Sent to Minors |
| SD - Cesar Ramos: Sent to Minors |
| TOR - Chris Aguila: Signed to a Minor League Contract |
| WAS - Ron Villone: Released |
| WAS - Collin Balester: Sent to Minors |
| March 14, 2010 |
| CHC - Mitch Atkins: Sent to Minors |
| CHC - David Patton: Sent to Minors |
| PIT - Brandon Jones: Sent to Minors |
| March 13, 2010 |
| HOU - Matt Kata: Signed to a Minor League Contract |
| MIN - Denard Span: Signed, ( 2010-2014; Opt 2015)(five-year extension) |
| MLW - Hernan Iribarren: Acquired Off Waivers From, Milwaukee |
| TEX - Eric Hurley: Placed on 60-Day DL, (Recovery from right shoulder surgery) |
| March 12, 2010 |
| TOR - Robert Ray: Sent to Minors |
| TOR - Brad Mills: Sent to Minors |
| TOR - Casey Fien: Sent to Minors |
| March 11, 2010 |
| COL - Todd Helton: Signed, ( 2012-2013)(two-year extension) |
| FLA - Ryan Tucker: Sent to Minors |
| LAD - Brian Giles: Retired |
| TB - Jake McGee: Sent to Minors |
| WAS - Shawn Estes: Released |
| WAS - Eddie Guardado: Released |
| March 10, 2010 |
| BOS - Nomar Garciaparra: Retired |
| BOS - Nomar Garciaparra: Signed to a Minor League Contract |
| LAA - Chad Orvella: Signed to a Minor League Contract |
| MIN - Brad Hennessey: Signed to a Minor League Contract |
| OAK - Jay Marshall: Released |
| SEA - Ryan Feierabend: Sent to Minors |