WASHINGTON – There are a handful of numbers on every pitching line that a starter can dissect after a night on the mound. Rookie southpaw DJ Herz is OK with looking past the strikeouts -- which he has racked up in the double digits twice this season -- and digging deeper into each at-bat.

“I love the quick outs because it’s always been hard for me to get in my career,” Herz said. “So when I get them, I love them. Getting quick outs, double plays, those are big for me, and I know the strikeouts will come.”

Herz overcame a 28-pitch first inning to deliver a 93-pitch, 5 2/3-inning outing for the Nationals in a 3-1 loss to the Rockies on Tuesday at Nationals Park.

“I think I’ve always been mentally strong in that type of area on the mound where I’m quick to forget it. I don’t really get upset. I just kind of control what you can control and move on,” Herz, 23, said. “I think that I’ve been doing a lot better of getting out of it, and then going about the game as, ‘All right, that’s it. It’s over, let’s move on.’”

Herz faced seven batters in the opening frame, but held Colorado to one run on an RBI single by Ryan McMahon. He bounced back to navigate through the scoreless second inning on 13 pitches to four batters.

From there, Herz retired the side in order in the third (eight pitches), fourth (10th pitches) and fifth (10 pitches) with a total of five strikeouts.

“I love getting out of there with nine, 10 or less or somewhere in that range,” Herz said. “It’s big to me because pitch efficiency is a lot with me. … With a team that swings like that, it was good to get some early outs.”

Herz held the Rockies off the board again until the sixth inning, when he allowed singles to Brenton Doyle, Brendan Rodgers and Nolan Jones, resulting in Jones driving in Doyle for the Rockies' second run with two outs.

Manager Dave Martinez made the call to the bullpen for right-hander Eduardo Salazar. Herz allowed three runs (two earned) off six hits, two walks and seven strikeouts in his 13th career start. His 93 pitches were the most since throwing 102 on July 7 vs. the Cardinals.

“He threw the ball in the first inning well, [but] the balls they hit were middle-middle,” said Martinez. “He settled down, started pitching really well and utilizing all of his pitches. He kept us in the game; this is the furthest he’s gone in a while.”

Tuesday at Nationals Park was a different result for Herz than his first time facing the Rockies on June 21 at Coors Field. That day, he gave up four runs (three earned) in 3 2/3 innings.

"That guy's pretty good,” said Rockies manager Bud Black. “He's got a good fastball and a good change. We got to him in the first and had an opportunity with [Brendan Rodgers], but that didn't happen. This guy gets more strikeouts than innings pitched. His hit totals are fine. He's got a good arm.”

In his six starts since the All-Star break, Herz has recorded a 3.07 ERA compared to 5.17 in the first half of the season. During that span, he has held opponents to a .216 batting average and tallied 34 strikeouts.

“He understands what he needs to do, he understands himself really well,” Martinez said. “He didn’t get rattled after that first inning. He knew he had to be a little bit more efficient, and he went out there and did that.”