Stan Kasten resigned as president of the Nationals:

There was no immediate reason given for his resignation. He will remain through the end of the season.

It very well be a non-baseball issue, such as an illness. It also may be that Kasten just hasn’t been that successful in turning around the franchise. This was his fifth season as president, and the team doesn’t seem that much closer to being a winner, especially with Stephen Strasburg on the shelf for a year.