The Washington Nationals climbed over .500 on Thursday afternoon with a dramatic walk-off win. The players, however, returned to the clubhouse to find out that they are now without a manager.

Washington manager Jim Riggleman resigned following the Nats' 1-0 win over Seattle, in the midst of what has the potential to be the best season in Nationals history.

Jim Bowden, who resigned himself as general manager of the Nationals in 2009, tweeted that Riggleman resigned because Washington had not picked up his option for the 2012 season.

According to Bowden, Riggleman told Nationals general manager Mike Rizzo that if he did not get a contract extension by the end of the game, Riggleman was going to resign.

Not surprisingly, the Washington front office is not happy at all about Riggleman's decision, and Bowden tweeted that the Nats are "shocked" and "disappointed" by the decision.