Okay, first off, as has been said, its a confidence issue. The guy misses, he looses confidence, so the next shot he's more likely to miss (and the GK is more likely to save, as his confidence is growing!) ... and you have a vicious circle which gets out of control early.
First, you're going to want to look at the way you interact with your players:
Communication and Psychological Warfare
Second, if you like being able to vent a bit, you're going to need to change the type of player you want: high Determination, high Work Rate players with the "Professional" personality descriptor respond much better to criticism than touchy troublemakers do.
Finally - have you gotten the 8.0.2 patch? Because this is something that was often complained about on 8.0.1, and was reportedly addressed with 8.0.2.
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