J Pat Carter/AP

Jayson Werth played three innings at Class A Potomac on Wednesday and still felt some tightness in his strained right hamstring, Nationals Manager Davey Johnson said. He is starting in right field again on Thursday and is expected to play five innings. (UPDATE, 9:20 p.m.: Werth went 2 for 3, both singles, with an RBI and played six innings in right field.)

Werth told Johnson that he played at about 60 percent on Wednesday in the rehab game. The original plan was for Werth to play four straight rehab games, upping each outing by the innings until he reached a complete game Sunday. But Johnson said Werth won’t play on Sunday.

Even then, however, Johnson said, there was “no possibility” that Werth re-joins the team in Atlanta during their three-game series there from Friday through Sunday. The hamstring has confounded the Nationals, as Werth suffered a set-back when playing a rehab game two weeks ago.

“Jayson may, after [Thursday], say, ‘I’m ready,'” Johnson said. “It just depends on how much he puts in today and how he feels. He’s still worried about that little bit of tightness in there.”

>>> Danny Espinosa played on Wednesday, his first game back from resting for five games after learning he had been playing with a fractured right wrist for a month. He went 1 for 4 with three strikeouts. According to Johnson, Espinosa didn’t have any new swelling in his wrist after the game and felt fine.

But the larger question is how well and long can Espinosa manage the injury and pain, and how much of it will affect his performance. Steve Lombardozzi, who filled in for Espinosa, is hitting 234/.254/.306 on the season. But in the five consecutive games played in Espinosa’s absence, Lombardozzi went 6 for 20 with two doubles and no walks.

Johnson did admit, for the first time, that the position, because of the injury, was still up for grabs. “We’ll see how [Espinosa] handles playing with a hand not 100 percent,” Johnson said. “Then I’ll make the decision then.”