I'm sure you all saw Mark Zuckerman report this morning that Tracy is headed to the DL and Corey Brown was flown to Miami yesterday to take his place. Mark covered the news angle, so this is just a quick post on Brown statistically.
Brown is currently in the midst of the best year of his minor league career with a slash line of .297/.399/.584. In short he's doing everything right at the plate: he's hitting for power + average and he's getting on base at just under a .400 clip. To give you some reference, he's getting on base more regularly than the two top Nats regulars in OBP: LaRoche and Harper.