The next three weeks will decide whether the Nationals are buyers or sellers at the July 31 trade deadline. But it’s hard to envision which way they’ll go.

The Nats (47-42) used a 28-11 run to enter the All-Star break sitting second in the NL East, though only a half-game ahead of the Phillies and one game ahead of the Mets. They’re leading the wild-card standings right now, tenuous as that position may be. Strong starting pitching and five weeks of mostly crummy opponents have given Washington some hope for a postseason berth.

But is this recent success really fool’s gold? The schedule will soon tell.

Washington begins a three-game series at Philadelphia (47-43) on Friday, followed by two games at Baltimore (27-62) and four games at NL East leader Atlanta (54-37). A 10-game homestand against the Rockies (44-45), Dodgers (60-32) and Braves follows.

The final game against Atlanta comes on Major League Baseball’s trade deadline. If Washington fails to significantly reduce Atlanta’s current six-game lead — or worse, falls further behind — then the Nats will be sellers.

Washington would need to break up an aging roster — 17 players are at least 30 years old — and maybe even trade Anthony Rendon before he becomes a free agent and bolts for more money like Bryce Harper did. That Nats owner Ted Lerner recently met with Rendon’s agent is irrelevant. Harper’s departure showed that nothing is certain until a deal is signed, so why watch a talented player walk away without gaining anything?

But if the Nats cut Atlanta’s lead to four games or fewer, then Washington should become a buyer and will need to pick up a reliever or two to take care of the seventh and eighth innings. The bullpen nearly buried this team at 19-31 earlier this season. Washington should even overpay if it has to like it did in 2017, when it got Ryan Madson and Sean Doolittle from Oakland.

After tons of injuries, a healthy lineup is once again producing, and starting pitchers are thriving. Max Scherzer is unbeaten in his last nine starts with a 0.84 ERA, while Stephen Strasburg is 6-1 recently and 10-4 overall.

The Nats will need a big bullpen move, but are understandably hesitant to do so before they know whether it will be worthwhile. With only one NL team and five AL teams at least 10 games back in the wild-card race, few clubs are willing to concede the season and trade a reliever. The next three weeks will sort contenders from pretenders as the trade deadline looms.

Maybe the Nats’ recent surge wasn’t a mirage. But they’ll need to prove it over the rest of the month. Otherwise, midseason will let them clearly see whether the team can regroup for 2020.

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