I suspect that Clay Matthews, realizing that the Packers were in the playoffs regardless of the outcome, and being double teamed on almost every play, either deliberately or inadvertently dialed it back a little bit against the Lions.
His dropped INT certainly indicates there might have been a little lack of focus on his part.
I'm not saying that Clay was dogging it, rather that he looked to be preserving himself a little bit. With playoffs still in question the previous week against Minnesota, CMIII played like a man possessed the entire game. Whereas the game Sunday night became just a little less important (although another division title ain't chopped liver) following Washington's loss.
I guess another way of saying this is that this past Sunday night wasn't "It is time" territory for our most important defensive player while he is still playing through a very tough injury for a pass rusher.
That changes starting this coming Sunday. Bloodline will be there, I have no doubt.