NFL and players' union officials have tweaked their joint concussion protocols following an investigation into how the policy was applied to Carolina quarterback Cam Newton in the league's season opener. The NFL and NFL Players Association announced Wednesday in a joint statement that the probe found no violation of concussion protocol from the Panthers' September 8 game against Denver, in which Newton suffered multiple helmet-to-helmet blows before being checked for possible head injury. Newton was slow to rise from a fourth quarter helmet-to-helmet hit that resulted in a Denver penalty.
