So far this season, it has seemed like the league has been going out of its way to protect NFL quarterbacks.
Last Sunday, Giants defensive lineman Justin Tuck was flagged for a penalty after driving Cowboys quarterback Brooks Bollinger to the ground on what appeared to be a clean hit.
A couple weeks before that, Steelers linebacker James Harrison was called for roughing quarterback David Garrard on a hit that looked almost unavoidable
But this high standard of quarterback safety did not follow Matt Schaub to the Metrodome.
The Texans quarterback was hit low twice by Vikings defensive end Jared Allen, causing Schaub to injure his MCL. On a third play, the Texans thought Allen brought down backup quarterback Sage Rosenfels with a horse-collar tackle.
The Texans have sent the three plays to the league office for review.
"Obviously, it's illegal to go low on the quarterback and we have three plays that we're going to turn into the league and we'll wait to hear back," coach Gary Kubiak said on his radio show on SportsRadio 610.
The NFL has created a rule specifically designed to stop players from diving at a quarterback's knees: "No defensive player who has an unrestricted path to the quarterback may hit him flagrantly in the area of the knee(s) or below when approaching in any direction."
Allen told reporters after the game that he didn't intend to injure Schaub when he hit the quarterback in the knee. Allen also said that he suffered a separated shoulder from a hit by guard Chester Pitts.
Schaub wasn't ready to accept Allen's apology, saying he thought the defensive end committed a cheap hit.
"Well, I think it was," Schaub said. "The ball was already gone and a player went for my leg, which isn't what they are supposed to be doing. So, that's all I can say."