It was only going to be a matter of time before this move was going to happen considering how quickly Jared Miller has climbed the farm system. Heading into the 2016 season, he had flopped as a starter and no clearly defined long term role. In order to stick around, Miller accepted a change to the bullpen and has taken off since. In 2016, he pitched to a 2.64 ERA and a 80/23 K/BB in 61 1⁄3 innings across 4 levels. He hit a speedbump at the end of 2016 in Reno, so the organization sent him to the Fall League where he dominated the competition. That got him an invite to Spring where he showed off his skills to the organization early in March. After being sent to AA, Miller had a rough start to the season but picked up on the dominance in both Jackson and Reno.
The Diamondbacks have rewarded his strong performances with a 40-man roster spot. The team had until 8pm on November 20th to protect players from the Rule 5 Draft. Miller would have been eligible for the Rule 5 Draft if left unprotected since he signed at the Age of 20 and spent 4 seasons in the organization. By protecting him from the Rule 5 Draft, the organization clearly sees he has potentially a bright future in their bullpen. Relievers rarely make excellent prospects due to the few amount of innings they can contribute compared to starting pitchers, although I believe Miller is a special prospect compared to other relievers. I do struggle to find a reasonable comparison for him at the MLB level, but I do think his upside is comparable to another 6’7” lefty with a dominant fastball-slider/cutter mix in Andrew Miller (not related). It’s unfair to drop the Andrew Miller comp on him, but there is a lot of optimism given his performances over the last two seasons.
Miller will get his chance to compete for a bullpen spot given the wide open slots available for competition. Jorge De La Rosa is a free agent and T.J. McFarland is a non-tender candidate, so there is definitely a need for a left-handed reliever in the pen. Miller uses his 6’7” frame very well, getting on a downhill plane with his fastball and inducing ground ball contact. He complements a mid 90s fastball with a mid 80s cutter, which he learned from another former Vanderbilt LHP David Price prior to 2016, which is an absolutely filthy pitch. The cutter is his main out pitch, and it generates a lot of whiffs when he’s able to command it. The combination of the ability to miss bats (35.8% K rate in Reno) and the ability to generate ground balls (50.8%) gives Miller a lot of upside in terms of being a quality back-end option.
At this point, there’s very little left for Miller to prove in the minors and the only step left in his development is seeing how he handles big league hitters. As a reliever, he has better numbers against right-handed hitters than left-handed hitters, although he’s been excellent against both sides of the plate. Miller isn’t strictly a LOOGY although they may start him off in that role to give him as soft a landing as possible to start his career. At the same time, it’s also not a great idea to hedge bets on a guy who’s never pitched in the majors before even with great numbers against the best prospects in the game and the bandbox of the Pacific Coast League and Reno. They should bring in veteran competition for Miller because he shouldn’t be handed a role, but I’m also confident he’ll pitch his way into the back-end of the bullpen by the end of the 2018 season.