According to FanRag Sports' Jon Heyman, Melancon is one of several relief pitchers the Nationals have "spoken internally about" as they begin to explore the market for available players.
The Nationals acquired Melancon in a 2016 deadline deal with the Pittsburgh Pirates, and he immediately slotted in as the team's closer.
During his brief time in the nation's capital, Melancon registered 17 saves, 27 strikeouts, three walks and a 1.82 ERA.
But once the offseason rolled around, Melancon bolted for the Bay Area and signed a four-year, $62 million deal with the Giants that includes a pair of $14 million player options for the 2019 and 2020 seasons.
For the Nationals, targeting a closer in advance of the trade deadline is a no-brainer.
To this point in the season, the National League East leaders have had five different players notch a save. Plus, none of those pitchers has more than three.
The Nationals could emerge as division champions again with that committee approach, but breaking through and securing what's proved to be an elusive pennant may not be possible if they don't have a reliable closer in tow.