Tyler Moore will get a chance with Jayson Werth out this weekend in Pittsburgh. (By Jonathan Newton – TWP)

While the Nationals re-inserted one middle-of-the-order bat into their lineup with the return of Ryan Zimmerman, right fielder Jayson Werth will likely miss the Nationals’ weekend series in Pittsburgh with a balky left hamstring, Manager Davey Johnson said. Tyler Moore, who is playing right field and batting sixth tonight, will likely take Werth’s place in all three starting lineups.

Werth talked his way into Thursday night’s lineup against the Braves, only to leave in the fourth inning with tightness in his left hamstring after he felt a slight twinge reaching for a ball in the outfield. Though hamstring injuries have landed Zimmerman and catcher Wilson Ramos on the disabled list, Werth’s injury is more mild and different in nature. He is confident the injury will not affect him beyond this weekend and Monday’s off day.

Werth missed two games in Atlanta with tightness in his hamstring and swelling in his left ankle, which he fouled a ball off of. Unlike Ramos and Zimmerman, Werth did not pull his hamstring. He had tightness in his thigh and upper leg, and it manifested in his hamstring. “It’s not a strain,” he said.

Werth will not be available off the bench tonight as a pinch-hitter, Johnson said.

With Werth out, Johnson prioritized jump-starting Moore. A power-hitting revelation as a rookie, Moore is 5 for 28 with four doubles, no homers, one walk and 12 strikeouts. The Nationals’ bench has seen fewer chances to contribute this year compared with 2012 because of a more stable lineup.

“I need to get him going,” Johnson said. “He’s close.”

Moore will play right field, with Bryce Harper staying in left, because of the dimensions of PNC Park. The deepest part of Pittsburgh’s stadium is marked with a “410” sign in left-center field, while right field features a high fence only 320 feet away down the line.

Elsewhere in the Nationals lineup, Johnson put second baseman Danny Espinosa back at second base after a two-day hiatus at the expense of Steve Lombardozzi. Espinosa is hitting .173/.212/.333, which caused Johnson to give him a break.

“I had a good conversation with him the other day,” Johnson said. “He has such a high ceiling, and I want him to try to relax and not do too much. This is going to be a big series for him. As long as he stays within himself, doesn’t expand, doesn’t swing at balls out of the zone, he’s going to have a big series.”

Johnson was noncommittal when asked if Espinosa would remain his primary second baseman going forward. But he did make clear he would give Espinosa every chance to deliver on his high potential.

“Why do you guys keep asking questions about what’s going to happen tomorrow and the next day?” Johnson said. “My job here is to have all 25 guys doing the things I know they’re capable of doing. Danny is not doing the things he’s capable of doing. Shoot, Adam LaRoche is not doing the things he’s capable of doing. But I know that they’re eventually going to get to that point where they start getting comfortable with themselves and the confidence is there. That’s my job. If I don’t give those opportunities to guys who I know are very capable, I’m not doing my job.”