You might say the pass rush was spotty at the least, not "at best". Look no further than 4 sacks for a 19 yd loss and enough pressure to cause an interception. (should have been 2)
Clearly, the cards have work on defense, but the pass rush and especially the blitz packages were enough to keep under pressure, a young, fast, strong and effective Newton for most the game. Newton stayed poised and was impressive on many levels. Even with 4 sacks and good pressure from the Cards D line.
You could, however, say... secondary was spotty at best.