Diaz gave up a solo home run to Kole Calhoun in the eighth inning Tuesday to blow his second save of the season in an extra-inning loss to the Angels.
The 23-year-old has been unable to build up any momentum in his first full season as the Mariners' closer, and his K/9, BB/9 and HR/9 have all taken a big step back from his 2016 performance. Diaz still has an electric 97 mph fastball, but he doesn't seem quite ready to join the ranks of the game's elite relievers.