The Nationals are looking for a reliable backup in case Danny Espinosa is injured or needs rest. (Barry Gutierrez/AP)

Desmond could be out a month or more with the injury, leaving Danny Espinosa as the Nationals’ lone viable option. In case Espinosa is injured or needs rest, the Nationals want a reliable backup who can fill in at shortstop.

The Nationals have discussed a list of 15-20 names in the mold of Marco Scutaro, Nick Punto and Jamey Carroll. The list also includes players at Class AAA who would be improvements over the Nationals’ infielders at Class AAA Syracuse.

The Nationals are currently trying to judge the acquisition cost of their targets and which players are available. The person with knowledge said a move could happen very soon.  

Middle infield is one of the Nationals’ least deep position at the higher levels of the organization. They have several up-and-coming players in the lower levels, including Adrian Sanchez, Rick Hague, Jeff Kobernus and Jason Martinson.

Interestingly, had 2011 first-round pick Anthony Rendon not been injured, he could have been a candidate to provide major league help already. But he fractured his ankle in the second game of the season at Class A Potomac, and is only now rehabbing in the Florida Gulf Coast league. (He’s homers in his past two games.)

 Otherwise, the Nationals remain committed to not giving away any of their top prospects for pitching help, and they see no holes to fill in their starting lineup. They are also checking out the market for catching depth, especially with starter Jesus Flores dealing with a sore lower back and backup Jhonatan Solano on the disabled list with an oblique strain.

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