Kutter Crawford Is Good

I'll be doing a full preview of the Red Sox 2023 season later when the season gets closer and the roster is a little more final. For now, I'll be diving deep into a couple of players nobody is talking about. First up: Kutter Crawford.

Kutter Crawford is good. That's a sentence that doesn't get thrown around often enough. There are a few reasons for that, but primarily because it isn't true. The first-year pitcher posted a 5.47 ERA in 21 starts games last season, both as a starter and out of the pen. As the number #1 proponent of all things Kutter Crawford, I'm here to tell you why the right-hander could be a useful piece for the Red Sox going forward.

Before I dive into why I think Crawford can be good, I want to point out that there's a ton of uncertainty around the roster right now. There are A LOT of arms on the team and Chaim Bloom has made comments about potentially adding another lefty. Somebody is going to have to take a back seat. Unfortunately for Crawford, he still has a couple of option years remaining so he can be shuffled back and forth without exposing him to waivers. However, the opening day pitching staff is made of glass, so the chances of Crawford making his way onto the roster at some point this season are incredibly high if he does start the season in Worcester. I think he's likely on the day-one roster, but he may have to start the season at Polar Park.

I'd also like to point out that I don't think Kutter is an ace. I don't even think he's a two or a three. He could maybe be a four or a five. What I'm really here to advocate for is Kutter Crawford out of the bullpen. They've added arms to the back end of the pen and have the depth where guys may be used in multiple roles, but I think Crawford is the perfect candidate for a Garrett Whitlock-type, multi-inning relief role. He just doesn't have that "out-pitch" against lefties to really be successful as a starter.

Last season, Crawford featured five different pitches; four-seam, kutter, curveball, changeup, and slider. The key to his success is the four-seam fastball. He threw it almost 40% of the time last season with mixed results. It averaged 94.5 MPH and came with a 31.7% CSW rate which included an 11.9% swinging strike rate. Those strike rates are elite for a four-seamer, and while the velocity is fairly average, it came all the way up to 95.7 MPH when pitching in relief. He was clearly leaving some energy in the tank when he knew he had to go through the lineup multiple times.

Okay, so the fastball has performed, but why? Crawford's four-seamer has elite "rise", due to the insane spin rate. I won't pretend to know too much about physics, but the gist of it is that with higher velocity and increased backspin, gravity doesn't affect the ball as much. The pitch isn't actually rising, because no human arm can throw hard enough, or spin the ball enough to counteract gravity while throwing overhand, but it appears to when compared to a normal pitch. Here's an example:

It doesn't look like much, but it's the key to Crawford's success. It's the perfect pitch. Top of the zone, 96 MPH with rise. If a hitter on either side of the plate can do damage on that pitch, I'll tip my cap and say good game.

Alex Chamberlain at Fangraphs did a ton of excellent research on "Vertical Approach Angle" (VAA), specifically for fastballs, and created a metric to adjust for pitch height, "Vertical Approach Angle Above Average" (VAA AA). By this metric, Crawford's fastball (out of the pen) is "flatter" than the average fastball and flat fastballs play well up in the zone.

Chamberlain also explains that the flatter the pitch, the more room for error. While Crawford's VAA AA is above average, it isn't quite elite enough to succeed over the middle of the plate. Here's the pitch plot from his appearance on April 23 (shown above):

There are some pitches over the middle of the plate, some of which were mistakes, but he mostly lived up in the zone and most of his misses were up. Without looking at any of his other pitches, it's no surprise that he was able to strike out five batters in three innings here, allowing just one hit.

The fastball has the potential to be his primary weapon. The issue is, the location isn't consistent enough. The velocity and the spin are always there, the command is not. In 2022, the fastball had a .310 average against it, mostly due to poor location. Here's another pitch plot, this time from an August outing against Baltimore.

He's all over the map with the fastball, and as a result, got hit around to the tune of eleven hits and nine runs. The good news is that command can be improved without sacrificing the stuff. He's just 26 years old and has one season under his belt where he was asked to move up and down between AAA and the majors, as well as the rotation and the pen. Some consistency and a full off-season of major league training could go a long way in improving his fastball command.

That's a whole lot of talk about one pitch, and he has four others. I promise the rest of this will be quicker. After the fastball, his next best pitch is his cutter. It's also important to note his name is Kutter, so if he didn't throw one, he'd have missed his calling. His namesake pitch won't blow anyone away, coming in at about 89 MPH. That's okay though, because it provides decent velocity separation from his fastball, and comes with solid horizontal movement. Take a look:

It's not the nastiest pitch, but it has enough movement to get swings and misses. Again though, it comes down to Kutter's ability to locate the pitch. When he misses, it's getting hit. He has to place an emphasis on getting the ball glove-side and keeping it low. It's easier said than done, but that's all it takes to be an effective pitcher for Crawford. He gets such great spin and movement on his fastball and cutter, that it's just a matter of locating. Fastballs up and cutters down, that's a recipe to get just about any same-handed hitter out.

So what about the other three pitches? He's used them each to varying degrees of success. Here's a look at that changeup:

Decent movement on this one in particular, and it managed to fool Wander Franco, so there might be something there. Overall though, the pitch doesn't have a ton of consistent movement and he had a tough time locating it. If he's going to hone in on a third pitch, I don't think this is the one.

He also dabbled with a slider, throwing it 77 times in 2022. It actually had decent results with a 20.5% swinging strike rate and an average of just .176 against it, but it's a really small sample and the O-Swing% was subpar. If that's the third offering, he'll have to make it more enticing to induce swings and misses or start stealing strikes by throwing it in the zone. The movement profile also doesn't quite have enough differential from the fastball to effectively fool hitters, although the cutter could serve as a bridge between the two. I don't think it's the way to go, but here it is anyways:

Last but not least, we have the curveball. This is the one that I can think could really take Crawford to the next level. Even better, I think Crawford knows this is the best third offering he has. Here's a breakdown of his repertoire by game:

It's not super evident from the graph, and the data is a little skewed because some of his appearances were in relief, but you can see around July, the curveball became his clear third choice. In his start on July 4th, he threw 20 of them, good for four whiffs and a 35% CSW. Here's one of those curves from that game.

An absolute beauty. Buried down in the zone. The curve has a ton of vertical drop to it and plays really well with the four-seamer up in the zone. Here's a look at the observed and measured spin on his arsenal.

You can ignore most of the information in the graph, what's important is the red (four-seam) and blue (curveball) bars. Particularly on the left, you can see that out of his hand, the spin on the curveball is almost a perfect mirror of the fastball. The human eye can't pick up the difference between the two, making it the perfect pitch to keep hitters off balance. He doesn't get a ton of swings and misses on the curveball yet, so he could need a tweak. Higher-velocity curveballs tend to get more swings and misses, so maybe adding a little oomph would help induce swings.

All in all, Crawford has the beginnings of a really good pitcher. Location is the key to his success, and it all starts with the fastball. If he can consistently keep the fastball up and play off it with the cutter and curveball, he can be incredibly effective, particularly in a relief role. I reached out to Kutter and asked if there was anything he was working on this off-season. He responded as succinctly as he could, "Winning as many games as possible". When Crawford is a central part of a really solid Red Sox bullpen in 2023, don't be surprised.