"What would happen if you tried to hit a baseball pitched at 90% the speed
"The first thing you see is a blinding light, far outshining the sun. This
gradually fades over the course of a few seconds, and a growing fireball
rises into a mushroom cloud. Then, with a great roar, the blast wave
arrives, tearing up trees and shredding houses. Everything within roughly a
mile of the park is leveled, and a firestorm engulfs the surrounding city.
The baseball diamond is now a sizable crater, centered a few hundred feet
behind the former location of the backstop."
The good news is that, according to the rules of baseball, the batter would
be deemed to have "been hit by the pitch and entitled to take first base."