I happened to be shooting pics at the UA/WSU game this weekend, on the exact play Nick Foles had his knee rolled over. When you zoom in on them, you see it unfold frame by frame.

Watch the left side of the defensive line. One of the lineman loses balance, and then seems to dive and roll directly into the knee. You can see Arizona’s #6 start on top and cut across the field making the pass reception. He’s already turning to run upfield by the time Foles gets hit.