The Houston Astros have a star in the making

To say the Houston Astros have an impressive bullpen would be an understatement, but “impressive” is so blasé. Let’s spice it up a bit. In 2016, the Houston Astros had one of the best bullpens in recent memory. That, of course, is through the run-deprived, DIPs-colored glasses of FIP, and comes as no surprise. When you own the best strikeout rate AND walk rate in the league, FIP tends to think the world of you.

How the Astros bullpen either led or finished near the top of the league in many pitching metrics is a story on its own, but let’s focus particularly on one pitcher. Not Ken Giles. Nor Luke Gregerson, Will Harris, Pat Neshek, or Chris Devenski (damn, this team is loaded with talent and #Content). We’re looking at the youngest regular reliever in the pen for the ‘Stros: Michael Feliz.

Last season, Feliz faced the third-most batters for the Astros in a role that varied from middle relief to setup. While he had a 4.43 ERA overall, he showed flashes of dominance, striking out 39 batters while walking just six in 30 innings of work in May and June. Sure, arbitrary endpoints, but, if you recall, it was around this time that manager A.J. Hinch hinted at wanting to work the young righty into some higher-leverage opportunities.

Feliz dealt with struggles and control issues, where I’m sure folks more familiar with the Astros than I cited his youth and chalked it up to the clichéd “growing pains.” His first appearance of the year against the New York Yankees, or an outing in July in which Feliz came out of the bullpen to walk three straight batters (the final two coming with the bases loaded), stand out as the most egregious examples.

What is so interesting about Michael Feliz is that, in 65 innings of work, he struck out 95 batters — the fifth-best mark in the American League among relievers. It is somewhat remarkable that Feliz, who had never fanned hitters at a rate higher than 28.6 percent at any level of professional baseball (regardless of the sample size) exploded onto the scene with a 35.2 percent strikeout, the 10^th-best rate in Major League Baseball.

We talk a lot about trying to find the true underlying skill/talent level of a pitcher, and that is what takes Feliz from interesting to intriguing. What I’ve neglected to mention thus far is that while Feliz carries with him a below-average ERA, he had an above-average FIP (3.24), xFIP (2.67), and DRA (3.51). Although Feliz’s home run rate last season wasn’t amazing, he did own a walk rate that was slightly below league average. Combine those with his amazing strikeout rate, and you’ll also find that all FIP measures peg his true skill to be much better than his ERA — especially xFIP, where his high HR/FB rate is normalized.

That is a lot of words just to say this: Both descriptive and predictive pitching metrics peg Michael Feliz as a much better pitcher than his ERA suggested. At face value, that sounds great. However, since he has only 73 career MLB innings (65 in 2016, eight in 2015) under his belt, it’s smart to be skeptical. It’s also tough to dismiss the role his high BABIP and home run rate had. Feliz was hit hard, and there should be a functional reason as to why. He was a good reliever last season, but finding this why could be the key to Feliz becoming an elite reliever.

To understand the why, first we have to understand what Feliz is working with. The right-hander owns a good mid-90s fastball — which he can run it up into the high-90s on occasion — a sharp-breaking slider, and a changeup. As the year went on, Feliz started using his slider more, causing him to essentially ditch the change. His FB/SL usage split was about 63/31, with changeups occupying the remaining percentage. In terms of actual outcomes, both his fastball and slider induced a ton of whiffs relative to his competition:

The z-scores function of Brooks Baseball is one of my favorite, and really highlights the swing-and-miss quality of stuff Feliz offers. Having two pitches that can post whiff numbers at or above one standard deviation from the mean is special, and his slider even does well to produce grounders (though that didn’t seem to benefit him all that much last season). As his high strikeout rate and pitch-type whiff rates allude to, he can deceive hitters at an elevated level.

Of course, we knew that Feliz could miss bats, but what about the times that he didn’t miss bats? How could such strong pitches struggle in overall effectiveness? The search for how he was hit so hard in 2016 begins with his batted-ball profile.

Feliz gave up a slightly higher percentage of ground balls than he did fly balls (42.1 and 36.8 percent, respectively). That doesn’t tell us much, though. You know what does? The wonderful world of percentiles. Using the (kinda) new FanGraphs splits, I pulled every reliever in 2016 with at least 25 BIP per batted ball category. From there, we will focus on hard-hit rate and wOBA. There were 158 relievers who met that qualification for line drives, 251 for fly balls, and 301 for ground balls.

This is likely not the most efficient method, as the crop fortunate (or unfortunate) enough to give up at least 25 line drives potentially differs in talent from the other two groups, but the point of this exercise is that I want to see where Feliz stuck out (if at all) in terms of outcome and quality of contact. The percentiles are set up so that a higher number means a better wOBA and hard-hit rate, and vice versa:

Two things stick out. The first is that Feliz’s grounders weren’t hit all that well, but from the looks of it they were able to find gaps in the infield. It’s likely the culprit of his high BABIP, as well. I wasn’t quite sure what to make of this, other than this could be an area we see regression benefit Feliz.

Another theory I had is that these balls, while not hit all that well, found their way into the outfield by beating the shift-heavy Houston Astros infield. So maybe the shift was ineffective while Feliz was on the mound. Again, though, that is pure speculation, and an area I’d love to look at deeper down the road.

The second is what really caught my eye — his fly ball percentiles. In comparison to other relievers, Feliz gave up a lot of well-hit fly balls that resulted in not-so-beneficial outcomes. Plenty of pitchers don’t benefit from fly balls and maintain decent overall numbers on the mound. Feliz is no exception but, in his case, the reason he was hit hard on fly balls runs parallel to an area he struggled overall. Just to give you an idea of where Feliz threw pitches that ended up as fly balls, here is his Brooks Baseball density map on fly balls:

That is…remarkably right down Main Street. That’s just a density map of the pitches that resulted in a fly ball, though. Without seeing every pitcher’s fly ball density map, I would assume it would skew toward the upper portion of the strike zone. His overall density map must be different, right? Well:

Michael Feliz’s pitches weren’t bad, he just left them in bad portions of the zone — getting poor results on occasion. Recall that I mentioned earlier that his walk rate is slightly below average, as well as just how well he can miss bats, and there really is just one conclusion as to why Feliz was hit hard in 2016. While he exemplified league-average control, his command was just not up to par. See: his league-average 46.2 percent Called Strike Probability (control) and poor -1.3 percent CSAA (command).

This might seem troublesome at first, but pitchers with good stuff are afforded the luxury of lacking command. We’re getting into an area well-covered by Jonathon Judge, Harry Pavlidis, and Jeff Long in their great offseason work over at Baseball Prospectus, but think about Noah Syndergaard. Thor can afford to leave a fastball over the middle thanks to his high velocity, and he can even get away with a location mistake on his hard slider when compared to someone like Phil Hughes.

Does Feliz have Syndergaard’s arsenal? No, although he still has above-average stuff. However, like Syndergaard, Feliz could get away with his fair share of mistakes in location. Not all of them, hence the high HR/FB rate, but enough to be indicative of a skill rather than luck. This is why his electric stuff should make Astros fans excited.

Has Feliz put the whole package together yet? No. In higher-leverage situations, Feliz struggled. He looked fatigued as the year went along. For that reason, he fell into a role down the stretch where he came in mostly when the Astros were trailing in the middle- to late-innings. That alone is not a good sign for an Astros team who has expressed interest in converting the youngster into a starter (though that likely also hinges on the development of his changeup).

It’s easy to fall down the rabbit hole of “Feliz isn’t even 24 yet and he struck out nearly 100 batters in 65 innings!” It’s easy to fall in love with Feliz by just suggesting that he make an adjustment and improve his command at the major-league level. It’s easy to say all that from where I’m seated, but it’s another thing to implement it, which is Feliz’s next step. Feliz added a couple of mph on his fastball last season, to the point where he nearly hit triple digits. Certainly, Feliz’s development didn’t end once he joined the big-league roster, and you could point to that if you’re looking for signs he can adjust at this level.

It’s a lot easier to increase velocity than improve command, but Feliz has already shown he has an incredible skill to miss bats. He was a good option out of the ‘pen for Houston in 2016, flashing some strong stuff. If Feliz found a way to put forth that same skill in 2016 while also making progress with his command, it would fortify an already phenomenal Astros bullpen. Simply put, Michael Feliz has an opportunity to turn into one of the most dominant relievers in baseball, and it hinges on the development of his command.