WASHINGTON — The Washington Nationals did not play a major part in this year's trade deadline scramble, choosing to take their new closer and run down the stretch with a veteran lineup they believe has not yet produced as much as it can and will.

While the New York Mets added Jay Bruce and left-hander Jon Niese, and the Miami Marlins sent back one of the starters they hoped would boost them into contention, the Nationals did not make a single deal Monday. They emerge from the deadline with all of their top prospects, a new closer and a few lingering questions: Can their offense produce enough? Will their bullpen, as constituted, withstand a pennant race?

Those answers will come in time, but the Nationals did fill their most immediate midsummer need by acquiring closer Mark Melancon from the Pirates for Felipe Rivero and minor leaguer Taylor Hearn. Melancon has more saves than anyone in baseball since he took over as Pittsburgh's full-time closer in 2013. He is a free agent after this season, and is not in the same elite tier as Aroldis Chapman or even Kansas City Royals closer Wade Davis.

But the asking price on Chapman was too high for the Nationals, and Davis, who landed on the disabled list a few hours after the Nationals traded for Melancon, or Andrew Miller would have required even more. The Nationals got an All-Star closer, with no baggage, without touching any of their best prospects.

But what about the rest of the bullpen? The ninth inning has not been the only trouble spot for the Nationals in the past week, and the other National League division leaders added proven pieces to their bullpens Monday.

The Nationals now have Melancon for the ninth and some combination of Shawn Kelley, Sammy Solis, Oliver Perez, Blake Treinen and Jonathan Papelbon to get them there.

The more immediate question seems to be how the Nationals will use Papelbon, who has struggled lately and never has had to pitch an inning other than the ninth since his rookie season. The Nationals also have internal options to bolster their relief corps. It is worth noting that, despite recent struggles, the Nationals bullpen has the third-best ERA in baseball this season and the fourth-best strikeout-to-walk ratio.

The lineup is tied for the fifth-most home runs in baseball and the sixth-highest Wins Above Replacement, though the Nationals' batting average and more advanced metrics place their offense in the middle of the major league pack in terms of production. The Nationals offense has not been awful, but it could be better. With options like Jay Bruce, Josh Reddick and others available in deadline deals, the organization decided to stick with the pieces already in place.

Trea Turner has shown himself to be a capable leadoff man, and Ben Revere is due for a breakout. Turner's impressive week lifted the Nationals from the least productive leadoff spot producers in the big leagues to the second-least productive. Barring any waiver deals, they seem willing to put their faith in Turner — or perhaps a Revere revival — for better production moving forward.