SAN DIEGO -- Even though Nationals left-hander Charlie Manning gave up the game-winning runs in a 5-2 loss to the Padres on Thursday afternoon, manager Manny Acta focused on the offense -- or lack thereof -- as opposed to the pitching.

The Nationals' offense is near or at the bottom of almost every statistical category, with Thursday's game a demonstration of the Nationals' struggles. Washington went 1-for-5 with runners in scoring position, and collected only four hits in the game.

"We need to score runs -- that's what it is," Acta said. "Even if Manning got the job done, we weren't going to win. We scored two runs and we were going to be tied for how long. Who knows? We just need to get something going offensively."

Outfielder Ryan Langerhans, who collected one of the four hits, said the Nats' position players want to get the job done with the bats, but they have to stop putting added pressure on themselves.

"It's tough because the pitchers are battling hard out there and doing a good job," Langerhans said. "Hitting is so weird. I'm sure it will get contagious. Somebody will come up with the big hit and we might have eight or nine runs on the board. We just have to keep battling."

It was the Padres who put the necessary runs on the board in the bottom of the eighth inning. With the game tied at 2, Nationals reliever Saul Rivera wound up having his second consecutive bad outing.

Kevin Kouzmanoff led off, and hit what appeared to be a home run over the left-field wall, but Langerhans leaped and caught the ball for the first out of the inning.

"It helped that we were playing no doubles -- I was pretty close to the wall," he said. "I tried to get myself lined up. ... I tried to make sure I timed my jump right. Sometimes you can lose it when you try to bring it back like that. I tried to make sure that I held on to it when I landed."

It went downhill after that for the Nationals. Rivera gave up consecutive singles to Khalil Greene and Michael Barrett. Acta brought in Manning to face the left-handed-hitting Jody Gerut. The move backfired.

At first, Manning was ahead in the count, tricking Gerut with breaking balls. But with the count 1-2, Manning threw a slider and Gerut hit it over the right-field wall for the win. It was the second time in three games that Manning gave up the game-wining home run to a left-handed hitter. Adrian Gonzalez was the first on Tuesday.

"I threw some good pitches early in that at-bat -- I threw some good sliders," Manning said. "Just that last one, I just threw it and it just hung over the middle part of the plate. Gerut put a pretty good swing on it. As soon as he hit it, I knew it was hit a long way.

Asked what adjustments he needs to make to get left-handed hitters out, Manning said, "When I get ahead of the guy, I really need to go ahead and try to put them away, instead of messing around and leaving them over the plate. I need to throw quality strikes, not just strikes."

The game began with promise. With Wil Ledezma on the mound in the top of the fourth inning, the Nationals took a 1-0 lead when Elijah Dukes hit a sacrifice fly to send home Lastings Milledge.

But left-hander John Lannan gave up the lead in the bottom of the inning. With the bases loaded, Edgar Gonzalez singled to right field to drive in Adrian Gonzalez and Kouzmaoff. Lanning lasted six innings and gave up two runs on five hits.

"He had that rough inning and that was it," Acta said about Lannan. "He made good pitches when he had to. I'll take that any time."

Padres reliever Cla Meredith couldn't hold the lead in the top of the seventh inning as he gave up an RBI single to Langerhans.

It was the last meaningful hit of the game for Washington. Acta said he will continue to be patient and hope that the offense will come around.

"These are the guys we brought to Spring Training," Acta said. "These are the guys we expect to have the offense going for us. They're just not getting it done.