If the Nationals know when Adam Eaton will return from ankle surgery, they’re not saying. Their plans for left field in the interim are unclear. (John McDonnell / The Washington Post)

PHOENIX — When Adam Eaton initially hurt his ankle in early April, the Nationals thought he might miss a few days. Even when they diagnosed a bone bruise, they didn’t expect he would need too long. They planned their interim left field corps accordingly, figuring they could easily piece things together until Eaton returned.

But now, after weeks of uncertainty about the extent of the injury finally culminated in ankle surgery Thursday in Wisconsin, the team has a clearer sense of how long it will be without Eaton. Though the Nationals won’t provide a timetable, the answer seems to be something along the lines of “quite some time.” So what do they do now?

“If Matty  [Adams] keeps swinging like he’s swinging, Howie [Kendrick] keeps playing good — those guys, they’ll get a chance to play left field,” Dave Martinez said Wednesday. “[Andrew] Stevenson has been doing well, too, so he’s going to get to play a lot more now. And hopefully we’ll get Goody [Brian Goodwin] back soon, too.”

In other words, the Nationals’ plan is to keep piecing things together as they have since the injury. Their best option to replace Eaton, top prospect Victor Robles, hyperextended his elbow in April. Because Robles is nearly big league ready, the Nationals felt they were covered in case of a long-term injury to any of their outfielders. His injury changed that.

But Wednesday, Goodwin swung a bat for the first time since being placed on the disabled list with a sprained wrist in late April. The outfielder is in West Palm Beach, and the Nationals hope his wrist will permit him to start hitting more regularly — then begin rehab games — fairly soon. Goodwin has proven himself capable of everyday duty, should the Nationals need him there.

In the meantime, Adams will probably play there against right-handers when Ryan Zimmerman is in the lineup. Kendrick will probably play there against lefties when Wilmer Difo can play second instead. Martinez can play the matchups.

Speculation will swirl about Juan Soto, the 19-year-old the Nationals promoted to Class AA Harrisburg on Thursday after he dominated in brief stints with Low-A Hagerstown and High-A Potomac. But Class AA carries some of the top pitching prospects in baseball, and will test his ability to adjust to breaking balls. The idea of Soto rising all the way to the major league level by the end of this season still seems far-fetched, particularly because the Nationals expect Robles to be healthy in time for a September call-up. Then again, the idea of Soto rising all the way to Harrisburg this quickly seemed absurd when the season began, too.

But Soto is not the solution, and he would likely not be ready before Eaton returns, anyway. The Nationals could decide to acquire a veteran outfielder to bolster their depth, much like they did with Alejandro De Aza, Ryan Raburn, and others over the past two seasons. Moises Sierra remains an option against left-handed pitching, though he is hitting .180 and has not looked particularly comfortable over the past few weeks. The Nationals could decide to replace him with veteran corner infielder Mark Reynolds, who is at Syracuse but hit 30 home runs last season and has played some outfield. Rafael Bautista filled in for a brief period. But the Nationals’ internal options elsewhere are not everyday ready. Anyone close — like Stevenson, for example — is already carrying a heavier big league load than anyone intended.

Because Eaton will not be gone for the season, and neither will Robles, the Nationals don’t seem likely to package many elite  young players for an everyday-type outfielder to replace them yet. Besides, the market is still unsettled, and by the time it develops as we near the trade deadline, Eaton could be nearing a return.

So for now, the Nationals have what they have — a clearer idea of their starting left fielder’s status, and no clear replacement for him in the interim. They will piece things together until one of their key pieces returns.

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