Progressional hitting is another great approach. If you're working with a certain hitter, start slow and work up to it. 1.) Start off a Tee... about 10 swings. 2.) Move to front toss, they shouldn't be afraid at this point. Distance: about 15-20 feet. 3.) Move L-Screen back about 10 feet and start throwing SLOWLY overhand, if they aren't scared at this point then you can gradually move back every 10-15 pitches. If they ARE scared, slow down velocity so they can get used to it. Note: It's the arm angle that is frightening. A right batter facing a righty pitcher can be afriad because the ball is released from behind the hitter's head and his line of vision. It crosses over the plate but the fear of seeing a throwing arm that's initially in line with their vision can be alarming. You can do it... perseverance and support with your players!