Both runs allowed by Hernandez came in the sixth inning. Pirates starter Zach Duke scored on a double by Jose Tabata, who would later touch home plate on a sacrifice fly by Andrew McCutchen.
"I knew it would be a tough game today. I had to make my pitches and keep the ball down," Hernandez said. "The Pirates are a good-hitting young team. You don't want to be relaxed on the mound and lose everything. It happened one inning and I left the ball up."
Thanks to their middle of the lineup, the Nationals would give Hernandez all the runs he would need by the fifth inning off Duke. With one out in the fourth, Adam Dunn took a 2-2 pitch and hit the ball over the right-field wall to give Washington a 1-0 lead. It was Dunn's third homer of the series.
"We're giving up too many home runs, but still solo shots that keep you in the game," Pirates manager John Russell said. "I thought we swung the bats OK, but we can't create runs. That's been our problem. Until we start scoring more runs, every pitch means something. The pitchers, their backs are against the wall too often. We need to start getting some offense."
It was Washington getting the offense. Two batters later after Dunn, Josh Willingham hit a homer to make it a two-run game.
"The Willingham at-bat, I made some really good pitches to him inside," Duke said. "Calls could have gone either way. Unfortunately, they both went his way, and he did a good job staying on the sinker away and hit it hard."
Said manager Jim Riggleman about the middle of the order: "They are run producers, they have a history of being run producers. We are fortunate to have them and line them up together like that. We have a chance to put some pressure on the other club."
The winning run was scored an inning later. After he singled with one out, Dunn advanced to second on a balk by Duke. Ryan Zimmerman then hit a ground ball near the third-base line. Andy LaRoche grabbed the ball and threw it away, allowing Dunn to score.
Mike Morse, who went 3-for-3 on the day, added an insurance run in the eighth with a solo shot. Morse, who is hitting .417 for the season, is making case to be in at least a platoon situation with right fielder Roger Bernadina. But Riggleman said the team is committed to Bernadina. The club would like to see what he could do for a full season. Morse said he understands the situation.
"I could pretty much see the situations where I could get an opportunity to play, when there is lefty pitching or my pinch-hit opportunities," Morse said. "That's my role on the team, I'm happy with it. I'm going to try to do the best I can."
After pitching three straight games, closer Matt Capps was given the day off with Tyler Clippard saving his first Major League game. It wasn't a big deal to Clippard.
"I was just happy to contribute a little bit," Clippard said. "Whatever inning I pitch, I'm having fun out there, and tonight I got the save. As a reliever, that's something I've accomplished in my career. It's a fun save."
Washington is now a game under .500 at 30-31. Last year, the Nationals didn't get their 30th victory until July 26.
"We work hard every day," Hernandez said. "We try to play the best that we could play. We need a lot of support from the fans. We try to win. With their support, we could be better."