Jack Leiter looks good but I can't help but notice how often he's a) blowing on his hand, then b) either licking his fingers or going to the back of his head to wipe stuff off his hair.
I suppose this is legal enough, but he's got excellent control (3 BB to 25 K in AAA this season) and one could only hope our guys have figured out a way to get good grip on the ball like this, to give them better control (or at least increase their spin rates) as well. `\_(")_/`