I love bullpens. There’s a lot of angst over the decline of the starting pitcher that I’ve never been able to empathize with. I love armchair strategizing about who a manager should tell to get loose and when to make a pitching change. I love the opener and the “filler,” the Josh Hader types that can come in and record six or seven outs without breaking a sweat.

It’s lucky then that I’m a Yankees fan. For the better part of my lifetime, the Yankees have made it a point of pride to have a shutdown bullpen, and 2019 looks to be no different as the team’s locked up two of the four best pure relievers on the market, agreeing to deals with Zach Britton and Adam Ottavino.

One of the things that’s fascinated me the most about relievers is the increasing homogeneity, or at least perceived homogeneity in the group. Everyone seems to throw 98 with a wipeout slider, and that’s a hard thing for a team that relies on relievers as much as the Yankees to deal with. When you are going to ask three or four guys to make an appearance every game, you have to keep different looks for the hitters, as any major league hitter will be able to adjust to the same offering over and over. The Yankees seem to recognize this too, and have built a bullpen that actually offers a pretty diverse skill set:

This is the basic pitch offering from the Big Six relievers we know the Yankees will lean on: Aroldis Chapman, Dellin Betances, Britton, Ottavino, Chad Green and Jonathan Holder. You can see that right away we can break the group into a couple of different buckets. Betances is a great example of the anti-fastball approach, using his combination curve/slider more often. Ottavino is kind of like that too, at least throwing breaking balls more than his fastballs.

Chapman and Chad Green, meanwhile, are traditional fastball-first guys, and especially work up in the zone. Look at Green’s plot against someone like Betances:

Green tends to attack hitters directly, over the plate and up in the zone, whereas Betances works much closer to the edge of the strike zone, and this is just with fastballs. It’s a completely different look, and if you’re a hitter who just saw Chad Green, Betances will offer something very different even on the same pitch type, forcing you to adjust.

And then someone like Zach Britton offers something completely different, throwing a “heavy” - see: high spin rate - sinker that is meant to be hit, unlike Green’s fastball or Betances’ breaking ball. Again, let’s isolate just fastballs:

We have another completely different look. You just hit against Chad Green who is throwing fastballs at your chest, and now Britton is in throwing much more down in the zone. Couple that with him coming from the left side and it’s impossible to predict a pattern in Yankee pitching.

Even when you break away from pitch type and location, the different Yankee pitchers still manage to vary their deliveries and involve different kinds of deception. Let’s look at the release points for three Yankee relievers with similar pitch offerings; in order Holder, Ottavino, Green:

Three pitchers, all throwing fastballs and sliders, from three different heights and spreads. You can see how tight the spread of a pitcher like Holder is, and then how varied Green’s is. Again, as a hitter, you might see two or three of these guys in one night, and for pitchers all throwing right handed, you have to find ways to stay deceptive. These varied release points, especially going from a guy like Holder to Ottavino - almost a foot of difference! - are key in that deception.

If you want a better “eye test” of that deception, here’s Ottavino’s release point:

And Holder’s:

See how much lower and flatter Adam’s arm angle is at the same point in delivery? Both pitchers throw fastballs right around 93-94, but they’re coming at the hitter from completely different points on the batter’s eye.

This will become even more important as the Yankees deal with a rotation that still has some weird question marks. Hopefully Luis Severino will be more consistent in 2019, but if not, more relievers will be called upon. James Paxton and CC Sabathia will almost certainly miss a handful of starts between them, and the “starters” that will fill in are types like Luis Cessa and Chance Adams, who don’t inspire much confidence. Having a strong bullpen will be more important to cover those holes as well.

And then there’s the playoffs, where for the last two years the bullpen has been the Yankees’ most consequential piece. It won them a Wild Card game and was instrumental in series against Cleveland and Houston, while the failure of types like Lance Lynn were a big part of dropping the ALDS to Boston last year.

The Yankees rely so much on relievers that they can’t afford to have a homogeneous group. They need pitchers with varied pitch offerings, velocities and usage. So far, it’s not hard to see that that was a goal of the offseason, and one accomplished at that.