Mariners promote RHP Reggie McClain to give the bullpen some oomph

It’s a dream come true for every minor leaguer to get their big-league call-up. In that sense, the Mariners have been a genie with a terribly hidden lamp this year, as 12 players have made their MLB debut for Seattle this year. As soon as tonight, a 13th member could join their ranks in 26-year-old RHP Reggie McClain.

McClain is a prospect, but only just, as his age and relief-only role limit him to a narrow ceiling at best. A year ago, however, he was far from even this. The 2016 13th rounder will be the the second Jerry Dipoto draftee to make the majors since the new regime took over, following Matt Festa. After once joking he would have his number retired in Modesto, McClain is headed to the bigs thanks to an offseason adjustment and his participation in “Gas Camp”, which targeted a few specific players Seattle believed had biomechanical adjustments that could rapidly accelerate their performance (see, Newsome, Ljay).

Did that camp involve injecting adamantium into McClain’s bones like Wolverine? Andy McKay has thus far dodged the question. The results have been a transformation of McClain from a low-walk rate, middling strikeout rate, high age for the level starter into a bullpen force. He’s now working in the mid-90s consistently, 93-96 with a sinking fastball that looks a little like this:

MiLB

The increase in velocity and deception has helped him run a significantly-improved combined 58.1% GB rate through 72.2 IP across A+, AA, and, for the majority of the year, AAA. That McClain has held his own in the PCL is largely a testament to his knack for getting the ball on the ground. In the best-case scenario, McClain can offer a similar set of results to Brandon Brennan, who seems to be a strong bullpen piece since his Rule-5 selection this winter, and is nearing a return from the IL.

Brennan’s go-to pitch is his changeup, but McClain leans on his breaking ball. As a starter, he had a curveball and a slider, but the two pitches appear to have blended a bit in the bullpen. He’ll add or subtract velocity at times and alter the pitch’s shape to back foot lefties or elude righties.

There are many solid relievers in the minors who are replacement-level or little more once they crack the bigs, and it’s easy to envision McClain struggling much like other minor league masters have. But a year ago this would’ve been laughable to suggest. This weekend in Houston, McClain will be the 13th Mariner to debut this year. Ga head, Reggie.