If plain sight isn't enough, which it is, the mouthful of blood proves it, and there is no biting his lip or tongue due to mouth piece, the only way to get a mouthful of blood is to get hit in the mouth.
Legal hit or not, Williams is officially on IR and his father says Williams will reevaluate his situation at the end of the year. This may be the end of his career. Really feel for the guy.
