If you know it's coming, you just cheat and start your swing early. And if you get much of the bat on it, you have a decent shot at getting a hit. You can't cheat on a sweeping slider or hammer curveball. I played against guys in HS who could bring it at 90+, but they usually had no other pitches. I could hit them (at least make solid contact). Hell, at that velo you don't have to take a full swing - just choke up a bit and try your best to "catch" the ball with the barrel of the bat. I was lost against anything with decent movement or contrasting speeds. If the fastball has good (just about any) movement, then yeah, that's a different story. EDIT: of course, this is assuming you have a respectable level of hand/eye coordination. I've played against kids who are in the pro's now. Faced a few kids who throw low 90s. Theres a huge difference between 90 and 80 mph. Now think of the difference it is from 90 to 100 mph. Maybe one or two or a few people on this forum played minor league ball or college ball might be able to get a hit off that. Besides for that the rest of this message board has about 0 shot. I had some small college looks, played on a very good high school team that won state. I doubt theres any chance i'd catch up to 100 mph fastball.