The Attempted Marianoization of Huston Street

You know the difference between control and command? Mariano Rivera is why the difference exists. Some pitchers are good at throwing strikes; Mariano Rivera was good at throwing Rivera strikes, which were simply strikes where Rivera wanted them to be. They looked a lot like any other strike, and pitch to pitch you wouldn’t really notice a difference, but over time, pitches pile up, and locations really matter. No one has located quite like Rivera, and you can guess the effects. Or you don’t have to, since Rivera’s career is complete and we have a full statistical record, but anyway. Because Rivera could locate, he could make certain numbers work in his favor.

Yeah, he struck guys out. Yeah, he didn’t walk guys much. Those are the basics. But Rivera was also skilled at allowing weaker contact than your average other guy. One of the reasons we’re usually skeptical of BABIP-suppressing skill is that most pitchers just aren’t good at hitting the same spots over and over. Rivera was one of the exceptions. He limited the singles, and he limited the non-singles.

Let’s take a look at something. PITCHf/x captured only the last few years of Rivera’s career, but Rivera was still outstanding when the cameras were installed, so we have a good amount of data. Let’s consider balls in play that Rivera allowed on pitches that were out of the strike zone. (Thank you, Baseball Savant.) You know what those balls in play are? They’re worse balls in play. Worse, relative to pitches over the plate.

• 2008: Rivera ranked first in baseball, with 56% of his balls in play being on pitches out of the zone
• 2009: Rivera ranked seventh in baseball, at 44%
• 2010: Rivera ranked first in baseball, at 54%
• 2011: Rivera ranked first in baseball, at 52%
• 2012: Rivera was hurt 🙁
• 2013: Rivera ranked 17th in baseball, at 42%

This was one of Rivera’s skills. Or, if you prefer, this was a reflection of one of Rivera’s skills — more than anyone else, he forced the hitter to hit on Rivera’s terms. Hitters generally knew what was coming, but the pitches that came hovered around the edges, and hitters are conditioned not to swing at those unless they have to, because they’re difficult to punish. So, Rivera was difficult to punish, and that allowed him to become Mariano Rivera and retire as the greatest relief pitcher in the history of the sport.

And this all obviously brings us to Huston Street. Now, Street doesn’t quite pitch like Rivera pitched. Kenley Jansen uses a cutter like how Rivera used his cutter. David Robertson’s cutter is probably the most like Rivera’s cutter, in characteristics. Street’s not that kind of guy. But if the numbers mean anything, Street is beginning to do something Rivera would consider familiar. Street’s a command reliever — he has to be, given that his repertoire isn’t overpowering — and he, too, has been forcing hitters to hit on his own terms. And he’s been trending in the right direction.

This table shows the same as the bullet points above, only instead of for Rivera, this is for Street. Of the balls in play he’s allowed, how many have come against pitches that were outside of the zone?

Season	Out-of-zone BIP%
2008	37.4%
2009	30.6%
2010	37.2%
2011	39.7%
2012	40.2%
2013	46.3%
2014	51.3%

Street mostly hovered around the high 30s. Two years ago, he took a step forward, and last season, he took another. Over the last three years, Street has the highest such rate in baseball, at 47%. Last season, he led baseball at 51%. Because Street is a reliever, this doesn’t mean the same as if he were a starter, with a starting pitcher’s sample sizes, but Street’s been known for his ability to locate, and this supports the notion that he’s locating better than ever.

Let’s make clear what doesn’t need to be made clear, probably: Street wants more of the ball in play on pitches out of the zone. During the PITCHf/x era, opponents have posted a .245 ISO on balls in play on pitches in the zone. Out of the zone, .127. And remember, that’s balls in play, not total at-bats, so that doesn’t count in strikeouts. Just 10 of 46 homers have come on swings at balls. Two of those were borderline balls low, right over the heart of the plate.

Regarding the heart of the plate, Street is coming off a season of just 9.3% of pitches thrown in the zone, over the middle. It’s the lowest rate he’s posted since we first started getting information. His rate got lower between 2011 – 2012, it got lower between 2012 – 2013, and it got lower between 2013 – 2014. You might ask, how does Street attack hitters? Very carefully. Here’s Street against right-handed bats:

And Street against lefties:

Sure, the locations are a little predictable. These are somewhat reminiscent of Rafael Betancourt. But then, weren’t Rivera’s locations a little predictable? And Street throws multiple pitches. Righties see fastballs and sliders; lefties see both of those, and a changeup, too. If Street’s too predictable, the numbers don’t show it.

This probably shouldn’t surprise you, but over the last three years, Street has allowed baseball’s lowest BABIP, at .219. Now, that’s not his actual BABIP skill. And Street is prone to giving up a dinger from time to time. But his career ERA is far better than his career FIP and xFIP, and his command only seems to be getting sharper. Between 2011 – 2012, Street dramatically reduced his rate of pitches thrown in the zone, yet he’s continued to post high strike rates. He succeeds on the edges, such that hitters have to offer at pitches on the edges, and if they don’t, Street’s command is good enough he might still get a strike anyway. Street seldom loses strikes in the zone, and he often finds them out of it. As another consequence of all this, Street is remarkably easy for a catcher to receive.

The sample sizes dictate that we wait and see. Rivera made a career out of getting hitters to put balls in play weakly. Street has lately done that, but it’s only recently started in earnest, so we don’t know if it’ll keep up. This is, as the headline says, an attempted Marianoization. But there are worse things to attempt, and the results so far are promising. Huston Street’s showing excellent control and command. He needs to in order to succeed, and, my, if that isn’t just the very best motivator.