Diaz pitched a scoreless eighth in Saturday's 4-3 loss to the Athletics, issuing a walk.
The closer got some action despite the non-save situation, with manager Scott Servais opting to deploy him after he hadn't seen any work since April 16. With the Mariners' offense underperforming overall thus far this season, save opportunities have been at a premium for Diaz, who's made six appearances and is 2-for-3 in save chances while also notching a win.