This is a little different than what you asked but maybe it can help someone...
My son took a bad hop in the eye last Memorial Day. Eye slammed shut and he was ugly for a couple of weeks. Thankfully, no structural damage.
However, when he came back to the field, he had the yips. Every time a ground ball would come to him, he'd flinch. He swore he wasn't doing it but there was some subconscious thing making him flinch.
So I got him one of those plastic face guards for when you have a broken nose:
http://www.muellersportsmed.com/noseguard.htmHe hated it. He thought he looked stupid. Maybe a little goofy, I'll admit but better than sitting on the bench.
Benefit number one was he could tell his brain now that he can't get hit in the eye again.
BIG benefit number two, the wings that go across your cheekbones, block you downward vision. He was forced to look down and stick his nose in his glove on every ground ball.
Byproduct of him being injured, he played the best defense of his life wearing that guard and now that it's gone, he still plays that way.