(J Pat Carter/AP)

Flores did not even take batting practice Sunday to rest his lower back. Johnson wants to make sure Flores is healthy enough that he will not have to leave in the middle of a game, as he did Friday night. The Nationals currently have four bench players and eight relievers, so they cannot afford to burn any position players.

“For him to get back in the lineup, I have to make sure he can go through batting practice,” Manager Davey Johnson said. “If he can go through batting practice and his back doesn’t stiffen up, I’ll put him back in the lineup. But I don’t want to have a situation where he starts the game and has to come out like he did Friday. That just defeats all kinds of purposes.”

On the field about 90 minutes before first pitch, Flores went through calisthenics in shallow left field. He said he was feeling better and wished he was in the lineup.

“I want to play,” Flores said. “I’ve been through this before.”

As the trade deadline approaches, the Nationals could perhaps use more catching depth because of attrition. Along with Wilson Ramos being out for the year since May, Jhonatan Solano, Leon and Carlos Maldonado have all spent time on the disabled list. With Flores’s balky back, the Nationals have to consider trying to add a more veteran backup.

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