UPDATE (5:42 PM ET): Washington's offer to Cespedes is for a 5-year deal, according to Rosenthal. The Mets, in contrast, are only willing to offer a 3-year contract. It is currently unclear if other clubs are involved in the bidding at this time.
Why this rumor makes sense
Since the Nationals were notably interested in adding Upton, it would follow that the club is still open to adding one of the best outfielders still available.
The Nationals have been seeking outfield depth all off-season, and Upton was not the first free agent outfielder the club pursued. Before he decided to sign a $184 million deal with the Cubs, Jason Heyward reportedly had a $200 million offer from Washington to consider.
Although the market for Cespedes is not clear, the Nationals could emerge as the favorite since they might be the only club open to giving him an extensive contract. Both the Mets and White Sox are thought to be interested in Cespedes only if he considers a short-term deal. Washington's offer is likely longer and more valuable.
Both the Phillies and Braves are rebuilding, leaving the Mets, Nationals and Marlins to compete for the NL East title. If the Nationals add Cespedes, their lineup could produce consistently against New York and Miami's pitching staffs.
Why this rumor does not make sense
While Cespedes could prove to be an upgrade for the Nationals, they might not have a place for him to play.
Washington recently acquired Ben Revere from the Blue Jays to be their leadoff hitter and there is a chance he will share playing time with Michael Taylor. Jayson Werth still has two years left on his deal, which includes a full no-trade clause. Bryce Harper will open the season in right field.
Cespedes or Harper could play center field, but the Nationals acquired Revere with the intention of having him lead off consistently. Revere and Werth could split time in left field, and the additional depth would give Washington an opportunity to give Harper regular days off.
It is unlikely an outfielder would be moved if the Nationals signed Cespedes, but Washington would have four potential outfielders if Cespedes is added.
Likeliness overall: 7/10
The Nationals don't necessarily have a spot to for Cespedes, but they could probably give him the largest contract of any interested team.