Most of the fields are too small. Specifically, they're too narrow.
DC United just opened up against San Jose Earthquakes and what Washington-area fans were treated to was a soccer game in which grown-ups appeared to be playing like a bunch of 5-year olds. Mob soccer. It's where all the little kiddies - or, in this case, adults (exception for the 14-year old Adu) - just put their heads down and follow the soccer ball wherever it goes on the field. Imagine a swarm of bees following around a cup of golden honey.
Most MLS soccer fields are played on NFL football fields. NFL football fields are about 53 yards wide - soccer fields should be at least 70 yards wide, at a minimum. Watch an MLS soccer game in a converted NFL football field and you'll see that anytime the ball goes out of bounds the player throwing the ball in, or taking a corner kick, is starting his run from up against an advertising board or from a non-grass surface. In short, there's just no room in these NFL-style stadiums to widen the fields any more.
The DC United soccer field is RFK Stadium - a football field - home of the Washington Redskins. Here are some measurements, in yards, including the dimensions of the most famous soccer field in the world - Old Trafford, home of Manchester United (the New York Yankees of soccer):
|NFL Football:||120 x 53 (+ 1 ft)|
|FIFA-recommendation:||115 x 75|
|Old Trafford:||116 x 76|
|RFK:||110 x 72|
Now, a couple of yards may not seem like a whole lot, but it makes a big difference. The bigger the field, the more players have to spread out. The difference in area (square yards) that needs to be covered between the FIFA recommended-field size and the RFK Stadium soccer field size is 705 square yards - that's 6,345 square feet for you city dwellers. That's a big difference, and it changes the game dramatically.
The sub-par field dimensions in the US are the dirty little secret of MLS. MLS has taken steps to correct the problem with the addition of a couple of soccer-only stadiums, like the Home Depot Center in Carson, CA, but we have a long way to go. Bigger fields will yield more quality play immediately.