Troy Vincent knows the game of football revolves around the quarterback.

The game has changed almost annually in recent years to aid offenses and protect passers, but the NFL’s executive vice president of football operations says those players need to protect themselves, as well.

“They have to know, when they get out of the pocket, when it’s time to slide, when they have that passing protection and when they don’t,” Vincent told Ron Clements of Omnisport. “So it’s both. Making sure we’re properly educating the defenders on when you have to let up and what’s a forcible blow, and then the quarterback, when you have protection and when you don’t.”

Several quarterbacks suffered significant injuries or blows to the head during the 2016 season, including Cam Newton, Derek Carr, Marcus Mariota, Ryan Tannehill, and Tannehill’s backup, Matt Moore.

Vincent said the league will continue to look for ways to improve protection for its marquee position, and acknowledged that defenders have adapted to the strike zone: the area between the shoulders and knees in which defensive players are able to target offensive ball-carriers.

“We’ve seen our players adjust extremely well over the last three or four years,” he said. “The league is driven by good quarterback play and defenders.”

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