He wasn't down by contact, his own player was pushed into him and he then fell, he could have gotten up and made a play. He was fair game. Actually, one of the interior defensive lineman got through and slapped McNabb's knee into the other, knocking him down. I don't know if the whistle blew, and I have no doubt the defensive player thought McNabb tripped over his own feet. An unfortunate occurrence, but a clean play nonetheless.
Just wanted to correct the record.
Someone else had mentioned that as well. I never saw that during the re-plays but it's entirely possible that one of the defensive guys got a hand on him low and nobody saw it.
I just take issue with people saying it was a cheap shot (and even the announcers saying it was a late hit) when the whistle never blew.