Kent professor finds MLB baseballs “juiced”

More perceptive Major League Baseball fans noticed a strange spike in home run rates between the 2014 and 2017 seasons. Major leaguers scored 6,105 points off home runs in 2017 compared to 4,186 in 2014. The 2017 home run numbers were comparable to the 2000 season home run rate of 5,693 points, which was during the steroids era.

To investigate this mysterious increase, childhood friends Tim Dix and Nathan Beals teamed up in early 2017.

Dix, who worked for ESPN Sport Science at the time, passed the project onto Beals, a former graduate student who was working on his dissertation under the guidance of Kent State chemistry professor Soumitra Basu. They started by looking at the composition of the baseballs used in the 2017 season and comparing them with balls used in the 2014 season.

The Department of Chemistry and Biochemistry collaborated with the Advanced Materials and Liquid Crystal Institute to scan the balls with magnetic resonance imaging and computerized tomography machines. 

Looking inside the balls and revealing their components exposed differences in density. 

More recent baseballs were less dense than the balls used in the 2014 season, causing them to fly about six inches farther than earlier balls when hit on a typical home run trajectory. 

The newer balls had been “juiced,” meaning that the baseball is lighter and less dense. 

These findings were enough for Dix to publish a feature with FiveThirtyEight.com, but Beals and Basu were not done looking for answers. 

“When you do a scientific study, it just doesn’t rely on one thing. You do multiple studies and try to verify the answers from different angles so that you get a comprehensive picture of what’s going on,” Basu said. 

Beals and Basu then examined the “pills” of the older and newer baseballs. A baseball’s pill is the bouncy ball inside of the red and white thread. Inside, it houses layers of rubber and cork. 

To analyze the pill’s components, they used scanning electron microscopy (which scans a materials’ electrons), energy-dispersive x-ray spectroscopy (used for chemical characterization), thermogravimetric analysis (used to measure thermal changes over an extended period of time) and carbon composition analysis (which measures carbon contents).

The research revealed the MLB was intentionally raising home run rates by changing the composition of the baseballs. The older baseballs had more silicon, sulfur and carbon in their pills. Chemical analysis showed material differences in the balls’ pills, which CT scans confirmed. 

MLB and its commissioner, Rob Manfred, have repeatedly denied rumors that their baseballs have been altered in any way to produce more home runs. Goodyear manufactures the rubber for MLB’s baseballs; they declined to comment.

Beals and Basu received press coverage from major news outlets like CBS Sports and CNN after the FiveThirtyEight article was published. Beals and Basu said they hope their research serves as a form of encouragement for Kent State students pursuing degrees in sciences. 

“The research [and press coverage] shows students in my lab that science doesn’t have to be so specialized and shown in a way that everyone can understand,” said Basu. ”They may not understand all the sophisticated techniques that went behind it, but the outcome is easily comprehensible.”  

The straightforward nature of Beals’ dissertation got potential connections excited to talk to him after hearing of his work.  

“Completing and publishing my findings provided me with a lot of new connections and work opportunities,” revealed Beals. “I hope this shows current students that chemistry, or any science, doesn’t have to be complicated and can potentially align with your interests.”

Hannah Davis is a sciences research reporter. Contact her at [email protected].