When A.J. Puk debuts today — and even though he has been in the bullpen since late-June, he is likely to pitch this evening against the Yankees — he’ll be the 51st player from the 2016 draft to play in the big leagues. He does so, despite missing more than a year recovering from Tommy John surgery, before every high school pitcher selected in 2016, other than Dustin May. Among 2016 draftee prospects still eligible to be on THE BOARD, Puk is ranked sixth; were I to include graduated players from that draft, he’d be seventh. Nick Senzel would slot ahead of him, but I’d still take the next half decade of Puk ahead of Pete Alonso, who I worry will have an early, precipitous decline phase.
Because I was with ESPN through the 2016 Draft, I don’t have pre-draft FanGraphs Puk content to link and quote in this piece. You’ll just have to trust that, relatively speaking, I was not crazy about him as a prospect. Left-handed stuff like Puk’s — he was into the mid-90s at times and had a consistently plus slider — is rare, but his velocity and control were inconsistent, he had conditioning issues, and he dealt with a back injury. He’d have been in my mix toward the back of the top 10, but I did not anticipate that, in retrospect, he would have been a justifiable pick at No. 1 overall.
Oakland drafted Puk sixth, and throughout the summer and fall after they signed him, his fastball remained in low-90s, mostly 92-93 but up to 95. By the following spring, he had already changed rather dramatically. From this spring’s Oakland’s Top 30 Prospects list:
Puk was soft-bodied and relatively unathletic as an amateur, but he arrived to Mesa in good shape and his landing leg was more stable throughout his delivery, leading to superior command than he had had at Florida. Additionally, Puk dusted off his high school curveball and reintroduced it to his repertoire. His feel for it returned very quickly, and it was comfortably average near the end of spring and gave him a fresh way of starting off at-bats the second and third time through a lineup. His changeup was also better than it had been in college, and looked like a potential plus pitch.
Puk reached Double-A halfway through 2017 and ended his year with 184 strikeouts across 125 innings, a 20-inning increase from the previous year. His velo kept climbing and by the spring of 2018, was sitting comfortably in the upper-90s. Purely on his combination of stuff and polish, Puk looked like he’d quickly rocket to the big leagues sometime during 2018, and the pleasantly surprising 2018 Athletics would have been motivated to add him to the rotation quickly.
But in March, he blew out. He had surgery in early-April and spent the next year rehabbing. By March of 2019, he was throwing bullpens. He started throwing in early-morning simulated games during Extended Spring Training, typically working just an inning or two against hitters too young to challenge him.
His velocity was back immediately. He has been 95-97 and touching 99 since his return, climbing the minor league ladder back to Triple-A. And Puk’s size, and the way he bends at the waist during his delivery creates huge extension toward the plate, adding about two picks of perceived velocity to each of his fastballs.
Here is the list of current lefty big league starters who throw that hard: _______
Blake Snell, at an average of 95.7 mph, has the hardest fastball among big league starters with at least 40 innings pitched this year. To find comparable left-handed fastballs for Puk, one needs to look toward relievers like Aroldis Chapman and Jose Alvarado to find peers.
And this is where a role-based caveat applies to Puk. Since his return from surgery, Puk has been in a one or two-inning role, mostly out of the bullpen. And not only that, but it’s been a well-manicured bullpen role, where he’s often had two or three, but as many as five or seven, days of rest between appearances. How his stuff will respond to on-demand usage during a playoff race remains to be seen.
I don’t think we’ll see fully-actualized, four-pitch Puk until next year. What he’ll be able to do with four pitches — multiple times through a lineup — won’t be needed in 17-25 pitch relief stints. Unless he somehow finds himself starting and working deep into games during the postseason due to need, I expect we’ll see a lot of fastballs up in the zone, and some combination of breaking balls beneath it. For now, I think Puk will be a valuable relief piece who works three to five weekly innings, and considering Oakland’s playoff-seeking predicament, those will be very important innings late in close, must-win games. Next year, with a potential innings limit in mind, he may be the best pitcher in their rotation.
Eric Longenhagen is from Catasauqua, PA and currently lives in Tempe, AZ. He spent four years working for the Phillies Triple-A affiliate, two with Baseball Info Solutions and two contributing to prospect coverage at ESPN.com. Previous work can also be found at Sports On Earth, CrashburnAlley and Prospect Insider.