NEW YORK, Sept. 18 (UPI) -- NFL Commissioner Roger Goodell has sent a memo to players mandating their conduct both on and off the playing field, the NFL Network reported.
He ordered all coaches and players do everything within their power to protect players from unnecessary injury, else harsh penalties will be imposed.
He added he wants NFL executive vice president Ray Anderson to let him know when his e-mail about the problem has been received by all team executives, coaches and general managers.
"Player safety on the field is important to all of us in the NFL (and) we need to do everything possible to protect all players -- offense, defense, and special teams -- from unnecessary injury caused by illegal and dangerous hits," he said. "Any conduct that unnecessarily risks the safety of other players has no role in the game of football."
Earlier this week, the league suspended Tampa Bay cornerback Elbert Mack for a helmet-to-helmet on Atlanta quarterback Matt Ryan last Sunday.
