CHICAGO (WGN) – While the Chicago Cubs look to close out the San Diego Padres at Wrigley Field in the MLB Wild Card Round, pitcher Shota Imanaga came into Game 2 in the second inning to pitch several relief innings.
Imanaga is known for having a pitch in his repertoire that becomes an optical illusion.
When Imanaga is on his game on the mound, many observers believe he’s able to throw baseball’s most dominant pitch, the mythical “rising fastball.”
In two years with the Cubs, Imanaga has thrilled MLB with the dominating and deceptive pitch.
Imanaga, 32, has mastered the so-called rising fastball which relies on physics as much as physical skill.
At the University of Illinois, professor Alan Nathan has become one of the foremost experts on the science of baseball.
“I used to work on experimental nuclear physics, but since my retirement, which is some number of years ago, I actually do research on the physics of baseball,” Nathan said.
According to Nathan, a pitched baseball is affected by three primary forces: gravity, drag and “the magnus effect.”
“The magnus force if it’s spinning that’s causing the ball to stray from its initial trajectory,” Nathan said.
Imanaga’s fastball maximizes the magnus effect, with the ball spinning backwards as it moves forward, to create the illusion of a rising ball.
“It doesn’t rise. It seems to rise from the batter’s perspective,” Nathan said.
No pitch actually rises, but Imanaga uses physics to play with a batter’s perception.
Marquee Sports Network Digital Content Reporter Andy Martinez has covered Imanaga’s career, as have a gaggle of Japanese journalists.
“So it makes it really hard for the hitter because they think they’re swinging at one part, one plane, but really the ball’s riding on a different plane,” Martinez said. “It’s a very fun physics analogy where it looks like it’s on a straight line, so you’re hitting it on a straight line that’s coming down at you, but it’s really on a straighter line that’s above it so usually you’re swinging underneath it.”
According to Nathan, Imanaga’s rising fastball is not actually moving upward against gravity. Instead, Imanaga throws a relatively slow fastball – around 92 or 94 mph – but he is able to place exceptional backspin on the ball, making it fall significantly less than a batter expects.
“Imanaga is sort of unusual in that his spin rate is high for a four-seam fastball and the speed is relatively on the low side,” Nathan said. “That combination of high spin and low speed gives rise to a lot of movement on his pitch.”
His pitches can cross the plate some 18 inches higher than a batter would expect, giving the illusion that the ball is rising like a ghost, almost disappearing as the batter swings.
“The batter, based on having observed many, many pitches, he sees what that trajectory is and if the ball ends up higher than he predicts based on his view of the trajectory he thinks the ball rises,” Nathan said.