Eight times hitters were completely befuddled by pitches up and in

It's said that the hardest thing in the world is hitting a baseball. I disagree. I think the hardest thing is actually stepping into the box. After all, you're facing a guy who can throw 90-something mph fastballs in your general vicinity. Who would choose to do such a thing? 
And yet, every day, hundreds of big leaguers do it so that they can bash dingers for our benefit. But how do they react when a pitch comes up and in? Here are eight of the best and most illuminating: 
Josh Harrison reacts as we all would
Let's begin with the reaction that each one of us would probably have if we were put in the batter's box.

Nick Ahmed's knees buckled so hard they could have been a belt
This is the closest thing you can get to a baseball version of being "posterized" in basketball. Santiago Casilla completely fooled the D-backs' Nick Ahmed with this curve that nearly touched the top of the strike zone. 

Andrew McCutchen isn't scared of anything
When Andrew McCutchen -- in his then-new Giants uniform -- faced former teammate Gerrit Cole in an Astros uniform, he was buzzed by a fastball from the curly-haired hurler. Rather than stepping out of the box, yelling at Cole or giving up on baseball, Cutch simply stared impassively at his old friend: 

Giancarlo Stanton doesn't care
When you're built like a human giant, the things that would bother other players are mere annoyances. So, when Giancarlo Stanton was hit by a Yefry Ramírez's pitch, it was like a fly on an elephant's back -- barely worth remarking upon. 

Carlos Gómez goes down
Meanwhile, Gomez chose the inverse of Stanton's reaction. He went down like a tree felled in a forest: 

Yasiel Puig wiggles
We all know that Puig treats the batter's box like his personal playground. So, it shouldn't be a surprise when his response to pitches that buzz him on the inside part of the plate is just as interesting. 

Adrián Beltré's jumping jacks
Whether it's a home run from a knee or just the good humor he's willing to have with his friends on the opposing team, Adrian Beltre is endless entertainment. And if he has to jump back from a pitch on the inside part of the plate, you'll see even more entertainment. 

Hernán Pérez's funniest bunt in history
A squeeze play is arguably baseball's most exciting, all-or-nothing play. Fail to get the bunt down and the onrushing baserunner from third is caught dead to rights. So, when the Brewers' Hernan Perez got into his bunting squat last year against the Reds, he displayed the kind of stick-to-itiveness that only the most competitive humans can pull off. 
And it's still pretty funny, too, as he collapsed to the ground after making contact.