Scientists Performed CT Scans on MLB Baseballs to Prove They Were Juiced

The “juiced ball” investigation has been gaining steam for months and may now be approaching critical mass. ESPN’s Sports Science teamed with academic investigators in an effort understand why baseballs might be traveling farther and the results were pretty stunning.

Much of the dialogue to this point has dealt with the outside of the ball, either the height of the seams or how slick the exterior was. Pitchers were very vocal about how the balls felt different — obligatory reminder that it’s important to check yourself occasionally — and weren’t moving as well as they had in the past, which they blamed for increasing blister issues and more hard contact.

MLB vehemently denied that anything had changed with the balls and continued to fall back on the notion that each horsehide spheroid remained within the league’s standards. Given how vague the official rules (page 5) are, it’s really hard to argue that the balls are in some way outside spec without cutting a bunch of them open and measuring everything about them.

But destroying them would fundamentally alter their structure, which is why researchers from USC — whom I have heard are pretty good scientists — ran CT scans on groups of baseballs from 2014-15 and 2016-17. They chose those periods because the home run phenomenon really became noticeable in the second half of the 2015 season.

They found that the core of the baseball (i.e., the pill) was far less dense in the 2016-17 baseballs than those from previous seasons. What’s more, this 40 percent decrease in density coincides with decrease in weight of about half a gram. While that might not seem like a huge deal, the researchers theorized that the changes could lead to a 0.6 mph increase in batted-ball velocity.

When considering the less dense core, lighter weight, and slicker exterior, scientists believe these newer baseballs could be travel 8.6 feet farther than their counterparts from pre-2015. Which, wow.

So imagine being Tyler Chatwood for a second. The new Cubs pitcher was throwing in the launchpad of Coors Field, where the environment already leads to decreased spin rate, among other things. For example, Chatwood’s cutter/slider spin rate was about five percent less when he pitched at Coors compared to away ballparks.

And when Chatty (which is now his nickname from here on out when I write about his pitches) had to throw baseballs that were lighter, slicker, and less dense? What a complete disadvantage.

Despite all this, I’m still not sure exactly what to think of the “juiced ball” stuff. The evidence is getting overwhelming here, and I just can’t wrap my mind around how MLB could really not expect their fans to figure out that they were making golf balls. Especially when those fans geek out over the science and numbers of the sport and have access to more than a hacksaw and a triple-beam scale.

Your move, Rob Manfred.