The Cody Bellinger signing by the numbers

Dec 7, 2022 - 6:00 PM

One of the stats that lots of baseball analysts love is max exit velocity. It’s not predictive of a baseball player’s ability on its own, but it demonstrates a ceiling of possibility. The baseball player who has hit a ball 112.9 miles per hour has shown us that he can mash a baseball under a certain set of circumstances, it’s just a question of whether those circumstances can be replicated again.

Which brings us to Cody Bellinger signing with the Chicago Cubs, a guy who just so happened to hit a baseball 112.9 miles per hour in 2018. That was one year before he would win the National League Most Valuable Player Award for the Los Angeles Dodgers at the age of 23. There are not many players out there with as tantalizing of a demonstrated ceiling as Bellinger. I am not being hyperbolic when I say that some of the smartest minds and projection systems in baseball saw Bellinger as not just a star, but a star on a potential Hall of Fame trajectory. Earlier this year Dan Szymborski shared the ZiPS pre-2020 Bellinger projection through 2029 in this piece at FanGraphs:

Dan Szymborski | FanGraphs

If you tally all those columns and add in the WAR Bellinger had already put up through 2019, that puts him at a career WAR of 69.2 through his age 33 season. Those numbers aren’t just good, they are Cooperstown numbers. However, ZiPS is a projection system, not a crystal ball, and there is a reason Szymborski titled that piece “The Bellinger Tolls for the 2019 MVP:”

Now, if this were a comedy movie, this is the point in the trailer at which you hear the record scratch, the narrator describes the humorous change of fortune, and then the music changes to an upbeat pop hit song with clips of how Bellinger gets back everything he lost and learns about the incredible power of friendship. But it’s not. Since that NL MVP season, he has hit .200/.271/.380 in over 1,000 plate appearances, only finishing above replacement level by virtue of the fact that he at least still remembers how to play defense. This is less Pixar and more Darren Aronofsky.

For a while, some underlying explanations gave hope. In 2020, the bullish explanation was that Bellinger had over-tinkered with his swing. In ’21, blame was placed on a shoulder injury from the previous postseason, one which required surgery and left him with a lot of physical weakness in his arm. After a course of weight training, Bellinger felt that his shoulder was back to where it was last August. We’re now a calendar year from when he said that, and he’s hit .195/.249/.368 since.

Which goes a long way to explaining why the Dodgers non-tendered Bellinger over the $20 million (or so) he was projected to make in 2023. Enter stage right a Cubs team whose top center field prospects are likely at least a year away and you have a match made in heaven for a $17.5 million, one-year chance to see if Cody Bellinger can get his groove back. Let’s dive into the numbers behind the deal to see if we can get a better idea of how it all might play out.

The Defense

You don’t need a lot of advanced metrics to know that the Cubs were not great defensively in centerfield last year (really, the last few years). Any person with eyes and a rudimentary understanding of baseball could tell you there were some problems for the Cubs defensively in center. That said, the numbers are still worth looking at because it’s probably worse than you think:

The 2022 Cubs were the worst team in baseball by defensive runs saved in center field, they were tied for the worst team in baseball by outs above average, they were second worst by FanGraphs defensive WAR metric. Cody Bellinger might have a lot of questions to answer about his offense, but the defense still plays. Depending on the leaderboard you are looking at, he had six or seven outs above average in centerfield for the Dodgers last year. By comparison, Rafael Ortega had -1 outs above average and Christopher Morel (who I love, but would like to see less of in center) had -4. This is a defensive upgrade for the Cubs, who really haven’t had a true centerfielder for multiple seasons.

The Offense

All of the question marks about Bellinger are on the offensive side. As Szymborski said above, there were question marks about the swing, a shoulder injury that required surgery, and subsequent calf and leg injuries that some have speculated could have also impacted his swing.

Look, I will be the first person to tell you that I am skeptical that the Cubs can fix a swing problem that the Dodgers could not fix. One of these teams has been a perennial playoff threat and the other broke Jason Heyward by tinkering with his (checks notes) swing. The Cubs rotate through hitting coaches faster than Hogwarts cycles through Defense of the Dark Arts Instructors. It’s not exactly an organization that can point to their approach to hitting as a strength.

However, Bellinger has already been working on his swing with some instructors who do have a track record of fixing swings, and the early video is worth checking out:

It seems pretty clear the injuries sapped some of Bellinger’s power. He hasn’t hit a baseball over 110 miles per hour since 2020. His max exit velocity in 2022 was 107.3 miles per hour. To put this in perspective with some other players Cubs fans are familiar with, Morel had a max exit velocity of 112.9 in 2022, Yan Gomes had a max exit velocity of 107.5. There is a Grand Canyon-like gap of power between Morel and Gomes. That is the gap that currently resides in the past five seasons of Cody Bellinger.

Make no mistake that the most likely outcome here is an offensive downgrade in centerfield. You can see the offensive contributions for the Cubs centerfielders combined compared to Bellinger’s 2021 and 2022 below:

The Upside

I view the most likely outcome of this deal as a defensive upgrade and an offensive downgrade. Given that the Cubs already lost a pretty valuable bat in Willson Contreras, that puts more pressure on the front office to add multiple bats this offseason. They likely believe one of those bats is Matt Mervis at first, but they probably still need to replace Contreras as best they can and add one of the remaining shortstops plus a designated hitter.

However, let’s dream a bit. This is Bellinger’s best chance to reestablish his value as an offensive contributor on the field and he has a pretty big incentive to do it now, since he’ll be a free agent again next year. He’s already demonstrated that he can hit at an elite level, the question is, can he get back to that level?

There was one bit of information on Bellinger’s Statcast page that I found intriguing. I still think it’s most likely he is a below average offensive centerfielder next year, but:

Statcast

I want to draw your attention to the numbers against fastballs in 2022 here and in particular, the wOBA column. As a reminder, wOBA is an on-base percentage that gives more credit for extra-base hits. An average wOBA is right around .320, above average is .340. You can see Bellinger’s collapse against every type of pitch starting in 2021. But his original problem is that .306 wOBA he put up against fastballs in 2020. I find it encouraging that his wOBA against fastballs in 2022 was back up to .341. That’s not MVP level Bellinger, but it is a sign that he was able to catch up to fastballs again.

He’s still ever so slightly above average at barreling the baseball (54th percentile, according to Statcast). If (and it’s a big if) the swing work he’s doing this offseason gets him back to a league average bat, it’s a plus. If it gets him back to an above average bat, as that improved wOBA against fastballs suggests, there’s an outside chance the Cubs got quite the deal to help them compete in 2023. Worst case scenario, if the rest of the offseason doesn’t come together, half a year of an even partially rehabilitated Bellinger should net Jed Hoyer and company a pretty nice return at the trade deadline. It’s certainly worth $17.5 million to find out.