This might be the low-hanging fruit of the Nationals' current roster, but Cory Abbott's time in DC should be up at the conclusion of the season. Abbott has been sent down and recalled from AAA Rochester several times over the past two seasons, and is really only up now due to injury/necessity. That being said, the Nationals' search for a long-relief pitcher who is capable of eating innings needs to extend beyond Abbott and other in-house options.
While players like Paolo Espino and Erasmo Ramirez served a purpose during their stints in DC, Abbott has never quite had the same value. Trading runs for outs has frequently been a trade the Nationals would make in the past few years, but Abbott has not exactly mastered getting the outs part of the deal.
Abbott has a 5.92 ERA in 83.2 innings over the past two seasons with the Nationals, including a 6.81 ERA this season. Abbott has 19 appearances this season and only 35.2 innings pitched, which is less than 2 innings an appearance. Not exactly what you want from your long reliever. Unless he can develop his arsenal to a back-end of the bullpen type pitcher, Abbott does not fill a need for this team.