As the St. Louis Rams will tell you, it only takes one quarterback hit to cause an issue.
Fans in Edward Jones Arena were left holding their breath this past Sunday as Sam Bradford, their franchise signal-caller and the former first overall pick in the 2010 NFL Draft, crunched the index finger on his throwing hand against a pass-rusher's arm.
Bradford left the game in the fourth quarter, after the Philadelphia Eagles had all but wrapped it up with a touchdown that made the score 31-13. Backup A.J. Feeley went in and threw five passes, four of which hit St. Louis' home turf, as the Rams' meager comeback attempt fizzled.
Nevertheless, it underscores the importance of pass protection. In a league where any hit on the passer can take the wind out of a franchise's sails, whether he's holding the ball or not, it's always true that the fewer hits there are, the better.
By calculating the rate at which each team's pass protection allows hits on the quarterback, we can shed a little light on how much the blockers (and the passer himself!) are flirting with that one crucial knock.