New study: ‘The MLB home run surge is not due to a juiced ball’
Attendance was down. The games were taking too long. But the balls were flying.
That led to this suspicion: Major League Baseball had secretly put a little more punch into its balls. More home runs were hit last year than in any other year in MLB history.
Commissioner Rob Manfred kept saying the ball had not been juiced, or for that matter changed in any significant way. Yet after outside studies showed a sampling of baseballs were different even while they complied with the specifications for their manufacture, the league commissioned 10 scientists and other experts to check the balls and the manufacturing process, and report back.
The single most important line in the report, released Thursday: “The MLB home run surge is not due to a juiced ball.”
However, the panel could not definitely say why the ball has been flying. Exit velocities — that is, how hard the ball was hit — were down last year, even as home runs were up. Launch angles were up slightly, “but only for the players with lesser home run talents,” the report said.
So why was the ball carrying? What could mean the extra few feet between a fly ball to the warning track and a fly ball over the fence?
The most likely culprit: reduced drag on the ball as it flies.
“If a ball has a center of gravity that is offset from its geometric center, the ball will wobble as it spins,” the report said. “As a result, manufacturing advances that result in a more spherically symmetric ball could have the unintended side effect of reducing the ball’s drag.”
Or not. That is a theory, and the committee continues its research into why the drag on the ball has changed.
In the meantime, Manfred said he would adopt committee recommendations that include standardized techniques for rubbing balls with mud before games and exploring whether to mandate that all ballparks install a humidor to store balls before use.
The Colorado Rockies and Arizona Diamondbacks are the only major league teams that currently use a humidor. In Arizona, where the humidor is in its first season, home runs are down significantly from last season.
In fact, home runs are down in all of MLB this season.
Follow Bill Shaikin on Twitter @BillShaikin
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