Nationals Manager Jim Riggleman, shown last month at Pittsburgh, said Saturday, “We’ve got to win some games when we’re not hitting, but you know, we feel like we’re going to hit.” (Gene J. Puskar/ASSOCIATED PRESS)

Finding an offensive middle ground has been difficult for the Washington Nationals. They’ve been shut out seven times, and they’ve scored at least seven runs in eight games.

They’ve had nights like Friday, when the franchise tallied six home runs and 17 runs in a single game for the first time since the Montreal Expos did it in 1978. And they’ve had days like Saturday, when two of their three runs were unearned in an 8-3 loss to the Baltimore Orioles that evened this interleague series at a game apiece.

“We’ve got to win some games when we’re not hitting, but you know, we feel like we’re going to hit,” Washington Manager Jim Riggleman said. “It’s a little bit repetitive to keep saying it, but that’s the way we feel. We feel like we’ve got good hitters who are going to hit.”

That may turn out to be the case, but it wasn’t evident Saturday. After combining for six hits, five runs, three home runs and nine RBI in Friday’s 17-5 win, right fielder Jayson Werth and second baseman Danny Espinosa went a combined 2 for 8 on Saturday.

The Nationals got on the board early thanks to a two-out error in the third inning by Baltimore first baseman Brandon Snyder (Westfield) that allowed two runs to come home.

The two runs were not nearly enough for Washington starter John Lannan, who was reluctant to mix in his curveball with his fastball, and paid for it in the bottom half of the third. After Lannan gave up a two-run home run to Orioles left fielder Nolan Reimold, he recorded two outs and then ran into more trouble.

With Adam Jones on first, Nick Markakis lined a single to left field that Laynce Nix misplayed — allowing the ball to get past him. By the time Nix recovered and returned the ball to the infield, Jones had scored and Markakis was standing on second. Nix’s error was Washington’s second in its past eight games.

Markakis then scored when designated hitter Vladimir Guerrero followed with a single.

Lannan recovered from the mishaps in the third inning, started throwing his curveball and notched five strikeouts in the following three innings. He tallied a season-high six strikeouts on the day.

“It’s tough,” Lannan said. “You want to stay there the whole game. It’s disappointing that I lose it a little bit, but you know, you’ve just got to keep on battling and find that rhythm and stick with it.”

The Nationals trailed by two in the sixth when designated hitter Matt Stairs came to bat with one out and two runners on base. Stairs, known throughout his 19-year career as a fastball masher, said he anticipated Baltimore starter Jeremy Guthrie throwing a change-up for the first time all game.

Guthrie did just that, and instead of waiting on a fastball as he is prone to do, Stairs lunged at the first-pitch offering and grounded into an inning-ending double play.

“You tip your hat to [Guthrie] making a good quality pitch and me being a dumb hitter and rolling over and hitting into a double play,” Stairs said.

Guthrie scattered five hits in seven innings and — save for the error-stained third inning — largely befuddled Washington’s hitters.

The Orioles scored four more runs in the seventh (two off Lannan; two off reliever Cole Kimball) to push their lead to six. The Nationals had no answers after the third.

“It was almost two different games for [Lannan], or about three different games,” Riggleman said. “He threw 15 pitches in the first two innings and then in the third inning had a hard time stopping that rallying and then found his curveball in the fourth inning and was unhittable for about three innings.

“And, you know, they got him in the seventh, but about five out of the six innings were sharp. It was just enough damage was done.”