In WCW, ECW, or NJPW, I'm pretty sure that he didn't take a chair shot that knocked him out for several minutes, then, when he regained consciousness, left him unable to stand for several minutes, while the company didn't have him checked for a concussion. Even with all of the concussions that could be hidden, it seems like there's a smoking gun in the fact that WWE claims to have records of no concussions when the above happened on their watch after the bizarre incident where HHH knocked out Benoit & a referee.