Tight end Aaron Hernandez suffered a leg injury when wide receiver Julian Edelman accidentally rolled up on him.
And with that, the 2012 offense took on a completely different look from the 2011 version.
Mike Reiss at ESPNBoston.com pointed out that the Patriots switched up their personnel tendencies rather drastically when Hernandez went down, but the differences were not just in terms of scheme, but personnel, too.
A lot has changed for this offense since this time last year. It went unnoticed because it happened so gradually: Piece by piece, starting with the offensive line, and then spilling its way onto the skill positions.
Not many have noticed until now, but those changes have added up slowly to the point where we could be looking at a starting lineup for Week 3 that features only four or five familiar faces from 2011.
The Patriots offense may continue with the two tight end formations that have been predominant in their offense over the past two years—signing free-agent tight end Kellen Winslow, Jr. indicates they're willing to do whatever it takes on that end—but regardless of the scheme, this offense has undergone a major face lift.
No wonder they couldn't find rhythm against the Cardinals after Hernandez left.
So what does this mean going forward? Hard to predict, but there could be some growing pains for this unit, and with how quickly this offense will have to grow without Hernandez in the lineup, those pains could prove debilitating against a Ravens defense that has given quarterback Tom Brady fits in the past.
Erik Frenz is the AFC East lead blogger for Bleacher Report. Be sure to follow Erik on Twitter and "like" the AFC East blog on Facebook to keep up with all the updates. Unless specified otherwise, all quotes are obtained firsthand.