Zat Knight was originally signed to help be a sparkplug for a reeling Colorado Rapids defense. Not to get too far ahead of themselves, though, the Rapids only gave him a single-season contract through the end of 2014. It's a move that makes sense, since his age and legendarily streaky style of play make him a big if for a spot in 2015.
Unfortunately, it doesn't look like he's going to be sticking around to see much of a future for the Rapids. Knight has been decent in spurts for Colorado since he joined, but the majority of the time he's been on the field it has ended in pain for everyone involved. A total of six goals against have been scored against the Rapids in the two matches he's been around, certainly not numbers to write home about. He was possibly the Goat of the Match against Chivas USA as well, which is a distinction that should never be won by a player who was in the Premier League a few years previous.
Even everyone's favorite intangible, leadership, isn't coming through in any meaningful fashion. Certainly can't leadership your way into a loss to Chivas.
Long story short, Knight is currently failing his Colorado Rapids audition, and he's failing it hard. He's got two games left to try and make it look like he's got anything left in the tank, but as far as I'm concerned at the moment, you can probably pencil his name into the likely sizable list of players on the chopping block for the off-season.