On NFL.com, Matt Cassel's afternoon was described as "an unbridled disaster." He was 9-for-15 with 92 yards and two interceptions. He also had a fumble on a third-quarter drive where the Chiefs were actually moving the ball. Then in the fourth quarter he was knocked out of the game with a head injury. After writhing around on the turf, he was taken off the field and replaced by Brady Quinn. The crowd appears to cheer.

Eric Winston, an offensive lineman for Cassel (and Quinn) was not pleased. Following the game, he called reporters over and spoke his mind and called those Kansas City fans out.

"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 to economic times, and they still pay the money to do this.
...
"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.

Winston had more to say, and you can find his whole statement over at Arrowhead Pride. It's worth a read. You can judge for yourself whether Chiefs fans actually cheered the injury in the video above. It's difficult to tell, but it sounds like there is an uptick in...excited chatter? Something had to happen to get under Winston's skin like that. It could be the crowd was just cheering for Brady Quinn, which seems just as odd as cheering for an injury.

Eric Winston: Fans cheering Matt Cassel's injury are 'sickening' [Arrowhead Pride]