Photo by afagen.

The Nationals crept over .500 with an exciting 1-0 win over the Seattle Mariners this afternoon — but the atmosphere in the clubhouse soured quickly, when manager Jim Riggleman announced his abrupt resignation.

Riggleman, who has been seeking a contract extension from the team, apparently told Nationals general manager Mike Rizzo before the game that if he did not receive an extension today, he would quit. Rizzo and the team chose not to extend that deal and so Riggleman followed through on his promise after the win.

The team does not have an interim manager in place, though Rizzo said that they would have one by tomorrow’s game against Chicago. There was no word on whether the team’s coaching staff would remain in tact.

Riggleman compiled a 140-172 record in two-plus years with the team.