It's not happening much at all in NFL football, since it's a major penalty if caught, and it's hard to hide.
I do hope helmet technology improves to handle inadvertent contact.
I do hope helmet technology improves to handle inadvertent contact.
http://bleacherreport.com/articles/2757235-rob-gronkowski-sa...
And furthermore, in that article Gronkowski is quoted as even preferring to take dangerous hits in the head like that, instead of risking re-injuring a bad knee. Not a great policy.