On the surface, what the Arizona Diamondbacks are doing doesn't seem that out of the ordinary. Sure, no one expected them to have the best record in the NL at 71-54, but stranger things have happened.But looking at it a little closer, it's actually kind of amazing what they are doing right now. At the time that I write this, even though they are 17 games over .500, they have been outscored by 20 runs on the season. That is kind of amazing when you think about it.
According to their pythagorean record (which is based on run differential), their record should probably look more like 60-65. Which would put them 4th in the division.
Obviously, that fact makes little difference to the Diamondbacks, but it is something to keep in mind because pythagorean record has usually been a fairly good indicator of future results (for examples see the New York Yankees and Chicago Cubs). That means that you probably shouldn't be surprised if the Diamondbacks slowly start to struggle, and eventually lose the division lead.
Of course, I've kind of been waiting for that for about a month now, but the Diamondbacks just keep on winning. Baseball is a funny game.