Mariners Roster & Staff
Transactions
| Date | Transaction |
| 08/30/13 | Seattle Mariners released RHP Aaron Harang. |
| 08/30/13 | Seattle Mariners optioned Erasmo Ramirez to Tacoma Rainiers. |
| 08/30/13 | Seattle Mariners optioned Xavier Avery to Tacoma Rainiers. |
| 08/30/13 | Baltimore Orioles traded LF Xavier Avery to Seattle Mariners for LF Michael Morse. |
| 08/30/13 | Baltimore Orioles traded LF Xavier Avery to Seattle Mariners for LF Michael Morse. |
| 08/30/13 | Seattle Mariners selected the contract of RHP Taijuan Walker from Tacoma Rainiers. |
| 08/30/13 | Seattle Mariners selected the contract of Abraham Almonte from Tacoma Rainiers. |
| 08/27/13 | Seattle Mariners sent C Mike Zunino on a rehab assignment to Tacoma Rainiers. |
| 08/26/13 | Seattle Mariners designated RHP Aaron Harang for assignment. |
| 08/26/13 | Seattle Mariners signed free agent RHP Tom de Blok to a minor league contract. |
| 08/26/13 | Seattle Mariners signed free agent RHP Ulises Perez to a minor league contract. |
| 08/26/13 | Seattle Mariners activated RF Franklin Gutierrez from the 15-day disabled list. |
| 08/23/13 | Seattle Mariners signed free agent OF Austin Schuetzle to a minor league contract. |
| 08/17/13 | Seattle Mariners optioned Jesus Sucre to Tacoma Rainiers. |
| 08/17/13 | Jesus Sucre roster status changed by Seattle Mariners. |
| 08/11/13 | Seattle Mariners sent CF Franklin Gutierrez on a rehab assignment to Tacoma Rainiers. |
| 08/10/13 | 3B Yordi Calderon assigned to Seattle Mariners. |
| 08/09/13 | RHP Carlos Misell assigned to Seattle Mariners. |
| 08/08/13 | Seattle Mariners sent C Jesus Sucre on a rehab assignment to AZL Mariners. |
| 08/07/13 | Seattle Mariners signed OF Brett Thomas. |
| 08/06/13 | Seattle Mariners released RF Jason Bay. |
| 08/06/13 | Seattle Mariners optioned Tom Wilhelmsen to Tacoma Rainiers. |
| 08/06/13 | Seattle Mariners signed free agent C Nick Ammirati to a minor league contract. |
| 08/06/13 | Seattle Mariners recalled Carter Capps from Tacoma Rainiers. |
| 08/06/13 | Seattle Mariners signed free agent SS Dan Kemp to a minor league contract. |
| 08/05/13 | Seattle Mariners placed C Jesus Montero on the restricted list. |
| 08/04/13 | SS Ivan Gonzalez assigned to Seattle Mariners. |
| 08/01/13 | Seattle Mariners traded 2B Robert Andino to Pittsburgh Pirates. |