NEW YORK -- After facing rain all weekend at Nationals Park, the Nationals encountered more inclement weather on Monday at Citi Field.

Their series opener against the Mets was postponed and will be played as Game 1 of a single-admission doubleheader on Tuesday, beginning at 4:10 p.m. ET.

Cory Abbott, who was slated to start on Monday, will take the mound in Game 1. Paolo Espino will make his originally scheduled start in Game 2. Erick Fedde is set to start the series and regular-season finale on Wednesday at 4:10 p.m. ET. 

The Nationals have won their last two contests against the Mets, both played at Citi Field on Sept. 3 and 4.