Welcome to Over the Monster’s One Big Question series. For those unfamiliar, this is something of a season roster preview where over the next 40(ish) (week)days we’ll be taking a look at each player on the 40-man roster prior to the season. If changes are made to the roster between now and Opening Day, we’ll cover the newly added players. Rather than previewing what to expect in a general sense, the goal of this series is to find one singular question — sometimes specific, other times more general — for each player heading into the coming season. We’ll go alphabetically one by one straight down the roster, and you can catch up with the series here. Today, we cover Marcus Walden.
The Question: Are we underselling Marcus Walden’s potential impact?
I’ve been thinking about the Red Sox bullpen a lot for the last few months because I’m a little sick in the head and I spend a truly disgusting amount of time thinking about the various corners of the Red Sox roster. When I think about the bullpen in particular, I tend to have two sections of players I think of. The first are the upper echelon guys, with Brandon Workman, Matt Barnes, Josh Taylor and Darwinzon Hernandez. And then there’s the wildcard types, which is basically everyone that is/was fighting for a job in spring training, plus a few guys like Tanner Houck and Durbin Feltman who could help a little later in the year. That leaves out two players. Heath Hembree is one, and I’m mostly fine forgetting about him to be honest. The other is Marcus Walden, who should probably be included in that top group.
It can be kind of easy to forget both because we are trying to forget about everything from last season as well as just the style with which Walden pitches, but he was pretty good last year! The righty made 70 appearances and tossed 78 innings out of the bullpen (23rd and 13th, respectively, among relievers in baseball) while pitching to a 3.81 ERA, a 3.72 FIP and a 3.83 DRA. After for park factors, those last three metrics were 21, 18 and 22 percent better than league-average. That is a very, very solid reliever with all three of the main metrics agreeing on that fact.
I mentioned above that part of the reason Walden flew a bit under the radar in 2019 is his style of pitching. In this age of fireballing relievers who misses bats, Walden’s two least-used pitches (per Baseball Savant) were his two varieties of fastball. He wasn’t a total zero in strikeouts, but he also was fairly well below what we think of in this modern era when we think of late-inning relievers.
Instead, Walden had his success by inducing hard contact and keeping the ball on the ground. In a year like 2019 when the ball was flying out parks all over baseball, the easiest way to protect yourself from dingers is to not allow balls hit in the air. Walden had a ground ball rate over 53 percent according to FanGraphs, ranking 26th among qualified relievers in all of baseball. It wasn’t just that he didn’t allow grounders, though. He also didn’t allow hard contact. By Baseball Savant’s measurements, he allowed an expected wOBA (which is based on contact profile) of just .302, and his barrel rate (which combines launch angle and exit velocity) was in the top four percent of the league.
It should go without saying that batted ball numbers can fluctuate some from year to year, especially for relievers. Walden threw a ton of innings for a reliever, and even his 78 was a fraction of what a starting pitcher throws over a season. That being said, there is some reason to believe Walden can sustain this. We intuitively know that pitches with movement are the most difficult to square up, and Walden throws with a lot of movement. His top two pitches in 2019, which accounted for 63 percent of his total arsenal according to Baseball Savant, were his slider and cutter. Both of those pitches had above-average horizontal movement, and his slider in particular was a monster with significantly above-average movement both horizontally and vertically. The results here were outstanding, too, as both his expected wOBAs and actual wOBAs (remember, wOBA is on an OBP scale) were under .300 and his average exit velocity on both pitches was around 87 mph.
Now, the flip side of using these two pitches so much is that it can be harder to throw strikes. Fastballs are easier to hit, but they are also easier for a pitcher to locate. When so much of your arsenal relies on offerings like a slider and cutter, it’s easier to fall behind and then let batters on with walks. That was the case for Walden last year, as he walked just under ten percent of the batters he faced and he was in the bottom seven percent of baseball in terms of zone rate, per Baseball Prospectus. You can live with that walk rate, particularly when you give up the kind of weak contact Walden allowed last year. Still, you’re playing with fire once you start getting to double digits in walk rate.
Besides hard contact, the easiest way to combat walk issues is by missing bats when you aren’t walking batters. We’ve seen guys like Craig Kimbrel, Matt Barnes and Brandon Workman all make these profiles work at times in recent years. Walden, as I mentioned towards the top of this post, is not an elite strikeout batter. Last season, he struck out about 23 percent of his opponents and was within a percentage point of league-average for a reliever. It’s fine, but for a guy you would like to be pitching in the late innings you’d like a little more. Fortunately, there are signs he can do that. For one thing, his overall swinging strike rate (per Baseball Prospectus) was just barely outside the top quartile in baseball. On top of that, his most used pitch (the slider) was elite at missing bats, racking up a 44 percent whiff rate. If he can work that pitch in more without sacrificing much, if at all, in control, that can take things to another level.
The Red Sox bullpen, if this season ever starts, is probably a bit underrated but is also missing elite, top-level talent. There are avenues for their top arms to get close to that, and if we were ranking them Walden would still probably be below the top four. That said, a slight uptick in strikeouts could get him closer than we’re probably giving him credit for, and his ability to induce weak contact with the slider and cutter provide him with a solid floor. Insofar as there is a top tier in this unit, it should be considered a group of five, not four.