SCOTTSDALE, Ariz.-- There are three high-end closers -- Aroldis Chapman, Kenley Jansen and Mark Melancon -- on the free-agent market. Coincidentally, the Washington Nationals are sorting through their late-inning options.
"The back of our bullpen is something we'd like to address," Nationals general manager Mike Rizzo said Tuesday at baseball's General Manager Meetings. "We also have guys we thought took another step in the progression last year."
Rizzo ticks off the arms that impressed him in 2016: Blake Treinen, Sammy Solís and Shawn Kelley. There's more pitching depth in the Minor Leagues. In other words, Rizzo might have an internal option.
"We would like to upgrade the back end of our bullpen," Rizzo said. "We think we will upgrade the back end of our bullpen. But that doesn't necessarily mean a lockdown closer. There is really good depth in the bullpen market. We'd certainly be open-minded about the seventh, eighth or ninth inning."
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Rizzo's most likely external move would seem to be re-signing Melancon, who made good on 17 of 19 save chances after being acquired from the Pirates at the non-waiver Trade Deadline.
But Rizzo may not be there just yet. He could spend his available dollars on a big-ticket outfielder (Yoenis Céspedes?) and move Trea Turner, last year's center fielder, back to his natural position of shortstop.

"We see Trea as an everyday shortstop in the big leagues, capable of playing very good," Rizzo said. "He's a unique player in that he gives us the positional flexibility to move him around the field. He's a dynamic player wherever he's played. For a guy that has played primarily shortstop his whole life, he adapted to second base and center field very well.
Nationals' free-agent targets: closer, catcher
"Because of the positional flexibility we have, we could upgrade ourselves at shortstop, in center field, corner outfield, put [Bryce] Harper in center. There's a lot of different ways we could upgrade ourselves. We're open to all sorts of different ways to upgrade the team."
Rizzo's other decision will come at catcher after allowing All-Star Wilson Ramos, who is recovering from knee surgery, to become a free agent. For now, veteran Jose Lobaton and 23-year-old Pedro Severino would start the season as the catchers.
"We're right now comfortable going to Spring Training with the two guys that we have -- Lobaton and Severino," Rizzo said. "[Severino] showed in his short stint in the big leagues that he handles a pitching staff very well. They love throwing to him. [In Lobaton], we've got ourselves a capable guy who has been through the rigors of being an everyday catcher in the big leagues and a guy who is an extremely good framer. He swung the bat very well when he came back from the disabled list."

If Turner does move to shortstop, that would force Danny Espinosa, last year's starter, back to a utility role or perhaps the trade market. He's a premier defensive player, but he hit .209 last season.
"I'm comfortable with Danny at shortstop," Rizzo said. "He's the player we thought he was. He plays good defense. He impacts the game defensively on the cutoffs and relays, on the basepaths, with his power. He brings a lot to the table.
"We know what his strengths are and his weaknesses. He's a player we always thought he could be. He played really solid defense at a premium position."