Welcome back to the One Big Question series here at Over The Monster. For those who weren’t around for last year’s series or simply forgot what it entails — there’s a lot going on in the world today, so don’t be ashamed! — here’s a brief reminder. Every day, Monday through Friday, for the next eight weeks we’ll profile a new member of Red Sox 40-man roster. Rather than simply going through a simple profile of their overall game and what they offer the team, we’ll focus on the one question that could very well dictate how their season will go in 2018. In order to keep the order objective and avoid side conversations like ranking the players on the roster, we’ll go straight down the roster in alphabetical order by position. In other words, we’ll go by how things are ordered here. If you miss any editions or would like to look back on some of last year’s, you can see all of them here. Today, we’re looking at Joe Kelly.
The Question: Is Joe Kelly ever going to post strikeout numbers to match his velocity?
The Red Sox have a bit of uncertainty in their bullpen, as I’ve talked about a bunch this winter. We know the players by now. Craig Kimbrel is a beast. Carson Smith looked solid in his first action back from Tommy John surgery. Tyler Thornburg is recovering from thoracic outlet surgery and is a complete unknown at this point. Matt Barnes has real talent but has failed to put it together, particularly in the biggest situations. Then there’s Joe Kelly, the guy who ZiPS projects to be the second best reliever in the bullpen. We all know what there is to know about Kelly at this point. For a long time he was stuck in the rotation despite everyone acknowledging he was a much better fit in the bullpen. He finally made the transition midway through 2016 and looked great, but then he came back in 2017 and simply looked fine. I think it’s hard to argue against Kelly being a viable major-league reliever, but we are still waiting for that (I have an unspeakable amount of self-hatred for what I’m about to say) great stuff to be backed up by strong strikeout totals.
Before we get into that, let’s take a quick look back at Kelly’s 2017, because it was actually really, really solid despite the noticeable lack of strikeouts. The righty ended up making 54 appearances out of the bullpen for a total of 58 innings last year and ended the year with a nice little 2.79 ERA. The peripherals didn’t really match that, though they also weren’t too bad depending on your metric of choice. Kelly ended the season with a 3.49 FIP, a mark that came in 19 percent better than the league-average pitcher after being adjusted for park effects. However, he ended 2017 with a 4.59 DRA, just over two percent better than the league-average pitcher. The biggest key to Kelly’s success, at least in terms of run prevention, was his ability to keep the ball in the yard. Largely thanks to his ability to induce ground balls, the former Cardinal allowed just three dingers on the year and posted a career-low 0.5 home runs per nine innings.
It’s the strikeouts we’re talking about today, though. Kelly has always had a bit of an issue with control — he walked more than four batters per nine innings in 2017 — but that can be more easily hidden as a reliever. Part of that reason is that stuff plays up in this role and strikeout rates should rise. Kelly’s has risen, but not to the heights we expected. After showing huge flashes in 2016, he struck out just eight batters per nine innings last year. For context, the average reliever last year struck out nine batters per nine.
As we start to look ahead to next year, and really the next few years for the righty who is about to enter his age-30 season, there is reason for optimism in this regard. For one thing, as I alluded to, Kelly showed off real strikeout stuff in 2016 after transitioning to a relief role. That year, he struck out over ten batters per nine innings as a reliever, though it came in only 17 2⁄3 innings. On top of that, he showed some flashes this past year with three separate months (May, August and September) with over a strikeout per inning under his belt.
Despite that reason for optimism, though, there is clearly still something missing from Kelly. The “great stuff” meme is a relatively well-known joke around the internet at this point, but there is some truth to it. Just watching Kelly pitch it’s hard not to be impressed. The fastball, of course, is the thing that really jumps out. He hits triple digits on a semi-regular basis and consistently sits in the high 90s. It’s a fastball that one would think should induce many more whiffs than it does. He pairs it with a couple of breaking balls that do induce a fair number of whiffs, though he also has a tendency to hang the pitch and then they get hit quite hard.
The main issue for Kelly is two-fold. For one thing, there just isn’t enough movement on that high-velocity fastball. While a 100 mph fastball is still incredibly impressive, it’s not what it once was. There was a time that all you needed was a triple-digit heater, but hitters can catch up to that now. Kelly’s is too flat, and if it catches the plate major-league hitters are at least going to catch a piece of it. Sure enough, according to Brooks Baseball, just about half of Kelly’s fastballs that induced swings were fouled off. It’s hard to rack up strikeouts if batters are consistently fighting off a pitch that you throw over half the time. A little bit more movement, even if it takes a couple ticks off the velocity, could theoretically go a long way for Kelly.
In addition to the movement, Kelly has also been a bit too predictable both in terms of when he throws pitches and where he throws them. He threw that big fastball 64 percent of the time in 2017, and over 70 percent of the time when the batter was ahead in the count. Players knew what was coming, which is enough to offset the velocity. He also leaned very heavily on the upper portion of the zone with the fastball. You can see his zone plot with the fastball here, and while it’s not uncommon for a pitcher to throw the high fastball a lot, it’s dangerous with one as flat as Kelly’s can be. Hitters not only can sit on a specific pitch, but they can sit on a specific pitch at a specific location. That’s a major reason why they are getting a piece of so many of his fastballs.
The Red Sox need at least a couple of pitchers to step up behind Kimbrel in the bullpen this season. Kelly may not be the favorite to do that, but we know he has the talent to do it. His ability to induce ground balls gives him a nice floor and will carve him out a role in this unit. If he can find a way to increase his strikeout totals, he can be a real late-inning weapon. We’ve been waiting his whole career for him to take that step, but we know he has the stuff to do it. He just needs to add a little more unpredictability to his game.