He didn't perform well, but neither did elements of Arrowhead Stadium. A handful of fans could be heard cheering as Cassel was taken to the locker room in the fourth quarter with a head injury.
Cassel's popularity is at an all-time low, but his right tackle, Eric Winston, came to the quarterback's defense during an impromptu news conference after the game. And Winston didn't pull any punches (via ArrowheadPride.com):
"We are athletes, OK? We are athletes. We are not gladiators. This is not the Roman Coliseum. People pay their hard-earned money when they come in here, and I believe they can boo, they can cheer and they can do whatever they want, I believe that. We are lucky to play this game. People, it's hard economic times, and they still pay the money to do this. ...
"But when somebody gets hurt, there are long-lasting ramifications to the game we play, long-lasting ramifications to the game we play. I've already kinda come to the understanding that I won't live as long because I play this game, and that's OK, that's a choice I've made and a choice all of us have made.
"But when you cheer, when you cheer somebody getting knocked out, I don't care who it is, and it just so happened to be Matt Cassel -- it's sickening. It's 100 percent sickening. I've been in some rough times on some rough teams, I've never been more embarrassed in my life to play football than in that moment right there.
"It's sickening. And I was embarrassed. I want every single one of you people to put this on your station and in your newspapers because I want every fan to know that. This is a game that's going to cost us a lot down the road. That's OK. We picked it, we deserve it and I don't want your pity. But we have a lot of problems as a society if people think that's OK."
This is just a portion of Winston's speech, which can be read in its entirety here.
Whether or not Cassel is getting it done on the field, the man who protects his blind side has a point.
UPDATE: Winston had more to say about the incident via Twitter:
Obviously i know not all 70k were cheering. And please don't act like the cheering started when Quinn came in.â Eric Winston (@ericwinston) October 7, 2012
I won't RT some of the mentions I got but I encourage people to go thru them. To the vast majority of you, thank you for the support!!â Eric Winston (@ericwinston) October 7, 2012
Follow Marc Sessler on Twitter @MarcSesslerNFL.
I've said what I wanted to say and i won't be talking about it any further. I stand by what I have said. I believe what I said.â Eric Winston (@ericwinston) October 7, 2012