About the Back End of the Yankees’ Rotation

The American League East is going to be tough this year. The Yankees are projected to win 81 games and yet still finish last, is how tough. That same win total, for example, would place a team in a tie for second in the AL Central’s projected standings.

There are reasons to be more bullish on the Yankees than the projections suggest. Plenty of smart people around the team are. The young core, consisting of Gary Sanchez, Greg Bird, Didi Gregorius, Aaron Judge, and Clint Frazier, provides a fair amount of upside. If the bullpen proves to offer as much depth as it is does excellence at the top, you’d have two-thirds of a really good team.

About the rotation, though. First, there’s the front three. Opening Day starter Masahiro Tanaka has been great since he signed with the team — among the majors’ top-20 starters by most metrics. Michael Pineda remains an enigma, a pitcher with elite strikeout-minus-walk rates paired with bottom-tier ball-in-play results. Even with his contradictions, though, Pineda can still provide value for a team that scores runs. At 36, CC Sabathia isn’t a front-line starter anymore, but a discovery of a cutter last year may have given him a few more years of usefulness on the back end.

And then what? Who will finish out the rotation this year? Who will step forward between Luis Severino, Bryan Mitchell, Chad Green, Luis Cessa, and Jordan Montgomery? If they’re any good, they could help fuel a surprise team in a tough division.

In the high-variance game that is young pitching, the best news for the Yankees is that they have five worthy candidates for the last two spots. Projections don’t love that depth, but there are some real reasons for optimism about the pitchers in that group. For the most part, for example, they all have velocity!

Whatever happens, two of these five will throw a ton more innings than the other three. If they’re good, they could help fuel a resurgent Yankee team. So let’s get to know them now, using a few key stats to better understand the strengths and weaknesses of their arsenals. Let’s have a few moving images, too.

It’s good to start with a strong fastball, and Severino has gotten our attention with a booming fastball with a little ride. The rest of the picture has been a story of stops and starts.

Early on, Severino was all nerves and gas. His slider was too hard. Over the course of the year, it got softer, added more drop, and started getting whiffs. If you measure just from July 1st, when he settled in with the bigger slider, he had a pitch with a 14% whiff rate, which is just barely above average.

Even if you give him a plus fastball and an above-average slider, you really need a third pitch from Severino. The change… it’s not so good. At least not for whiffs. It’s below average by movement and velocity, and it didn’t get better as the season went on. In fact, he stopped trusting the pitch. Here’s the hope, though: that the pitch is actually in the 90th percentile when it comes to arm-side movement, as it proved to be last year. If so, that’s good for grounders. Sure enough, Severino had a 46% ground-ball rate on the changeup last year, and some months where it only got grounders.

If Severino puts it together, it’s because he gets grounders with the change, and whiffs with this type of slider.

Bryan Mitchell throws the ball hard, and he’s probably in the cat-bird seat for the fifth-starter role. He’s pitched more innings than anyone else this spring, and has had a strikeout per inning and four strikeouts per walk, so the results have been fine.

But the fastball isn’t as good as Severino’s — and might not be as good as Chad Green’s, either. When it comes to fastball spin, you mostly want a lot of it, but you can also succeed with very little spin, since that usually adds drop. Mitchell’s in that deadly halfway spot, and he doesn’t add movement to make it great.

His curve is great. It’s hard and has tons of movement, and you can even toggle the parameters to make it even more interesting. Among the 78 curveballs that average more than 81 mph, Mitchell’s seven inches of drop ranks ninth.

We don’t know what makes a cutter great, but at least Mitchell has a hard cutter. So far it’s had average results, with a 10% whiff rate. Curves aren’t known for their whiffs, so the 10% whiff rate on his curve is only a bit below average. He had a great debut for the Yankees, but unless Mitchell has plus command, or the splitter on which he’s working this spring is legit, he doesn’t have an obvious road towards excellence. For what it’s worth, he ranked in the 72nd percentile on BP’s Called Strikes Above Average, but didn’t have plus walk rates in the minors.

If it’s not all called strikes on the curve, it’s probably on the splitter to keep Mitchell overperforming his prospect pedigree. Here it is, in action, this spring:

Though it didn’t work out as awesomely for the last Green(e) in New York, and they both had multiple sliders and questionable changeups, I have hope for this year’s version. For one, his fastball is better. This fastball might be the sneaky best in the crew, actually. Severino’s has more gas, but very few spin it as well as Green. That’s how Green got an insane 16% whiff rate on his fastball last year.

The slider and cutter are different pitches, there’s no doubt. There’s six inches of drop difference between the two pitches, and six mph of velocity. The slider has good drop and velo, important qualities for a slider, so we can believe his 15%, above-average whiff rate on the pitch. The cutter gets half the whiffs, but it got a 50% grounder rate against lefties, and he didn’t give up a home run on it.

It’s possible those two pitches will be enough with the great fastball, but we’re probably still hoping for more. You may have heard this one before, but Green throws a splitter that he could stand to throw more often. Right now, it’s about perfectly average over the 19 he’s thrown. It’s not super impressive to the eye, either:

Cessa doesn’t have a single pitch that would beat out the standouts above. His fastball ranks behind all three or four other contenders for the back end of the rotation, his slider looks almost exactly average, his curve has some giddyup but little drop, and though his change has a good 10-mph velocity gap, the movement isn’t sufficient enough to make it above average.

In sum, it looks like Cessa could be a decent back-end guy, but he doesn’t have the upside of the guys ahead of him. His upside won’t come from adding another pitch, at least: he already has those. Given his lack of spin, it might make sense to drop the arm angle and go for movement over velocity and spin. If he does add grounders to an average slider and three usable pitches, he could easily be a good fifth starter.

For now, he’s a sixth or seventh starter who can wow you every once in a while with a beautiful tight slider like this one from last year:

There’s been some pushing for the least experienced member of this crew to get a job. While it’s true that he’s been pitching well this spring (13 strikeouts and 2 walks in 14.2 innings), and has been showing real improvement (his slider has more depth now), I’m not sure he’s leap-frogged anyone just yet. Eric Longenhagen, while appreciating the improvement in the slider, still thought that the pitcher “lacks a true swing-and-miss secondary.” I’m not sure “Montgomery’s command of a diverse pallet of junk should allow him to negotiate through big-league lineups multiple times” is a booming recommendation.

As River Avenue Blues points out, those spring numbers have come in the second half of games, when the competition thins. There’s an open spot in the bullpen, and maybe the Yankees will use Jordan Montgomery as the left-handed multi-inning middle reliever to complement the returning Adam Warren. Baseball, it seems, is producing more 100-inning relievers like this, and it might be the best place for a guy with command of multiple pitches, no real out pitch, and this spot on the starting-rotation depth chart.

There’s still the fact of his improvements this spring. he’s up to sitting 92-plus by his own account, so maybe he’ll have above-average velocity to go with a good curve and that deceptive delivery. Maybe this slider will be the out pitch he needs to make his way into the rotation?

This collection of arms isn’t built on a collection of top-10-prospect types. Most of these are finds, players who have pushed their way into this opportunity by producing. They each have their own set of flaws that have kept them off those lists, but they also have their strengths that make them possible breakouts in the future.

Will Green’s high-spin fastball, paired with two breaking balls, help him to continue putting up good strikeout rates despite the lack of a changeup, or will he improve his change? Will Mitchell’s splitter take hold? Will Severino learn to use his changeup to induce grounders?

It’s an interesting group of pitchers — each is almost an archetype of possibly undervalued starters. In Severino, Mitchell, Green, Cessa, and Montgomery, you have your velocity-over-everything guy, a high-velocity curveball dude, a spin-rate king, a kitchen-sink starter, and a deceptive, way-over-the-top guy. There isn’t a great changeup in the bunch, really, and “does he have a changeup?” was once a dividing line between the rotation and the bullpen.

For any of us following the group, we probably have our favorite, and so I’ll admit to being partial to Green. He has three pitches, even if one is a cutter, and the spin and velocity to get whiffs. He doesn’t have command issues, and if he trusts the splitter more this year, that’s just gravy. He’s starting in a great place with that fastball. If I had to pick two, and Severino was going to start the season in the minors, I might just add Montgomery, who has never relieved before, to see how his deception and newfound stuff will work against major leaguers.

At the very least, it does seem likely that one of these will step forward and shore up a hole for the Yankees this year. Start with (diverse) quantity, and you should find your quality eventually.