HOW THEY MEASURE THOSE BIG BLASTS
HINT: IT’S NOT WITH A RULER
ANAHEIM, Calif. — The days when Mickey Mantle’s moon shots would be assessed by a man and a tape measure are long behind us. As a matter of fact, neither manual instruments nor human beings took part in the instant read on Aaron Judge’s mammoth home run Sunday at Yankee Stadium.
Seconds after Judge stunningly cleared the bleachers in left-center field, word went out on MLB.com’s various apps: The homer traveled an estimated 495 feet, longest in the major leagues this season. The quick reading resulted from the MLB.com Statcast system that has been in place since 2015 — a system instituted by people, obviously, but one that doesn’t require people to operate it in real time.
“We capture the flight of the path based on radar as far as the radar will allow us to track it,” Tom Tango, senior data architect of stats for MLB. com, said Monday in a telephone interview. “If the radar loses it, we project beyond it based on the physics.”
The radar, installed in all 30 bigleague ballparks, tracked Judge’s jack for only 211 feet because of its epic height; the ball evaded further detection like an enemy space craft zooming out of the periphery. So to finish the measurement and get the ball’s “natural” distance — how far the ball would have traveled unimpeded, if it hadn’t struck a fan positioned behind the bleachers who tried to catch it — Statcast relied on the exit velocity of 118.6 mph and its launch angle of 28.4 degrees.
“It was almost pure backspin,” Tango noted. “Often when you pull a shot in that direction, it might hook more, and when you hit it straight away, it might slice. [Judge] pulled it and it stayed in that line. It was like one of those golf shots where you hit it and it goes exactly where you want it to go.”
The adva n ce d technology has enhanced the eternal debate of who hits them the hardest and the longest. The Statcast folks opted to go with the projected distance for homers, rather than its distance to its precise point of impact, because they believed most fans preferred that.
“All projectiles follow a certain path based purely on its launch parameters,” Tango said. “All you need is a limited amount of data to create a polynomial equation that would extend out to whatever you want.”
Weather doesn’t factor into the equation, as the Statcast people assert that wind, for instance, is not constant in one direction, especially in a semienclosed structure, nor is it constant at each elevation point. The projection, for those home runs that evade full radar measurement, derives solely from the physical attributes of the batted ball.
And if a ball, let’s say, gets knocked down by the wind into a flyout at the warning track, then there is no projection involved. The radar provides the exact measurement, much as it would for a laser that stays in play by hitting the Green Monster, Fenway Park’s 37-foot-tall left-field wall.
A day might arrive when this process will be regarded as primitive as you might now think of the tape measure.
“We’re always in a constant state of improvement,” Tango said. “We’re always trying to make it better and better. It’s a matter of setting up all the different priorities that we’re going to go after.”
We’ve come a long way already, though. It’s our loss that the likes of Mantle, Babe Ruth and Josh Gibson can’t take a few at-bats in the Statcast era.