Though they already have a closer, so.
The main hang-up for these Jonathan Papelbon/Nationals rumors is that Papelbon only wants to close, due to a vesting option in his contract being attached to the number of games he finishes, and the Nationals already have Drew Storen (Paps also has a no-trade clause but he says that won't be a problem). Nevertheless, they are apparently closer to getting him:
Sources: #Nationals making progress on acquiring Papelbon from #Phillies. Papelbon has said he will only approve deal if he can close.