I've told a player who really got down on himself, "the pathway to success requires challenges that don't go our way. Without that, we can't achieve an understanding of how to improve. Learning what not to do is often more valuable than luck that results in getting away with a mistake. How we handle our emotions can help or hold back our improvement. Also, angry emotions displayed whether on the field or in the dugout, will always help the opposing team feel more confident and bring down your team's confidence. Our displayed negativity will result in their displayed positivity. Keep negative emotional outburst in check. After a poor at bat, return to dugout, do not throw helmet. Angry outburst will be viewed as weakness by the opposing team.
Body language screams. It can scream out weakness and can also scream out, I'm bullet proof no matter what happens. How would you like to be viewed?"