Tom Brady had his knee run into by Bernard Pollard in Week 1 of the 2008 season, and since then we've seen rules protecting quarterbacks get stiffer. You can't touch their helmets, you can't tackle them low, you cannot hit them hard unless they pretend they aren't a quarterback for a second.
The thinking was that we were seeing all these quarterbacks injured and QBs, as you know, are the faces of the league. Guys were getting hurt and it was bad business.
Yet it doesn't seem to have helped.
The 2015 NFL season has seen a lot of QB injuries. Andy Dalton (Bengals) is the latest, breaking his thumb trying to make a tackle and will most likely miss the rest of the regular season. He joins Tony Romo (Cowboys), Joe Flacco (Ravens), Josh McCown (Browns)
Peyton Manning (Broncos), Andrew Luck (Colts), Drew Brees (Saints), Sam Bradford (Eagles), Jay Cutler (Bears), Marcus Mariota (Titans) and Ben Roethlisberger (Steelers) have also missed time this season. You also had Geno Smith (Jets) injured with a punch to the face and a broken jaw prior to the season.
That's one-third of the NFL that's lost their starting QB to injury. Some have come back, some are lost for the season and some are in limbo. Several are Super Bowl winning quarterbacks.