The Mariners announced Monday that left-hander Jhonathan Díaz went unclaimed on waivers following his recent DFA. He’s been assigned outright to Triple-A Tacoma. Because Díaz has been outrighted in the past, he has the option to reject this assignment in favor of free agency.
Díaz was only selected to the 40-man roster late last week. The 29-year-old made one appearance with the M’s, allowing a solo homer in a 1 1/3-inning appearance. He appeared in exactly one game as a Mariner last year, too, and pitched exactly 1 1/3 innings in that outing as well. Overall, he’s made seven big league appearances with Seattle dating back to 2024 but otherwise served as rotation depth in Tacoma.
Prior to his run with the Mariners, Díaz pitched in parts of three seasons with the division-rival Angels. He’s logged a total of 47 2/3 innings in the majors across his six partial seasons. In that time, Díaz owns a 4.72 ERA, 15.1% strikeout rate, 12% walk rate and 45% ground-ball rate. Lefties have been terrible against him (.210/.301/.339), while righties have pummeled him at a .318/.408/.519 clip.
Díaz has similar run-prevention numbers in parts of six Triple-A seasons (4.79 ERA) but has posted better rate stats in the upper minors. The 6’0″, 170-pound southpaw has punched out 20.2% of his opponents in 517 innings of Triple-A work while issuing walks at a quality 8.3% clip. He’s induced grounders at a better-than-average rate (47.9%) and done a fairly nice job avoiding home runs (1.06 HR/9). Díaz relies primarily on deception and weak contact, as he’s lacking in terms of pure stuff. The lefty is averaging just 86.9 mph on his sinker and 87.9 mph on his four-seamer this season.
Even if Díaz accepts the assignment, he’ll become a minor league free agent at season’s end unless he’s added back to the 40-man roster and sticks all winter. Given Seattle’s enviable pitching depth, that seems unlikely. He’ll probably find himself on the open market one way or another this winter.
