PITTSBURGH -- DJ Herz has only gotten better as his rookie season has gone along, and his most recent start was the surest proof of that growth.

In the Nationals’ 5-3 win over the Pirates on Saturday afternoon in Game 1 of a split doubleheader at PNC Park, Herz held the Bucs without a hit through five innings, and then reliever Robert García carried that bid into the seventh before relinquishing a two-out single to Nick Gonzales.

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As has been the case throughout this season, Herz was unafraid to throw his four-seamer, pounding it for 57% of his offerings. The Pirates couldn’t pick up on it. Of the 24 swings he drew on his 50 four-seam fastballs, only two were put in play. Herz finished with five strikeouts to three walks on 87 pitches.

Herz’s final strikeout put it in perfect perspective, as he got Bryan De La Cruz to expand -- and look quite foolish -- for a swinging strike three on a four-seamer well into the other batter’s box. At 1.67 feet from the center of the plate, it is the second-farthest four-seamer out of the zone to induce a swing from a left-handed pitcher this season.

“I don't know if we've seen a young pitcher like that vary the speeds of his fastball: 92, 94, 96, back to 92, went back up,” Pirates manager Derek Shelton said. “He did a nice job at the top of the zone, and we just did not adjust to it."

Herz gave a lot of credit to his changeup, which has been a difference-maker in his rise up the ranks since being an eighth-round Draft pick out of North Carolina prep ball in 2019.

“I thought the changeup, it was probably one of the better days it’s been all year,” Herz said. “I was really turning it over and I was throwing it for strikes a lot, and if not it was a competitive miss.”

In two of his past three starts, Herz has put aside his struggles beyond the third inning to finish strongly. He threw five innings with just one hit allowed on Aug. 25 in Atlanta, and after grinding through an emotional start against the Cubs on Aug. 31, he bounced back with the first hitless start of his career against the Pirates.

“I love DJ’s start days,” closer Kyle Finnegan said. “He’s fun to watch.”

Herz has had a taste of a no-hitter before. He started for the High-A Myrtle Beach Pelicans while in the Cubs’ system on June 23, 2021, against the Columbia Fireflies and keyed a combined no-hitter.

On paper, his effort then wasn’t too different from what he showed against the Pirates in Game 1: five innings, no hits, four walks and seven strikeouts.

But Herz is a much more complete pitcher now vs. then, and the numbers are showing his continued progress at the MLB level.

First half: 5.17 ERA, 1.40 WHIP and .271 average against in 31 1/3 innings

Second half: 2.86 ERA, 1.09 WHIP and .177 average against in 44 innings

“I think it’s just going out there and pitching, knowing that you’ve got the stuff to do it,” Herz said. “Just stay in the zone. The in-zone whiff is there. Everything plays in the zone, so just staying in the zone is the big key.”

Herz is having his innings monitored closely this season. He hit 111 1/3 last season across Minor League ball and the Arizona Fall League, and he’s now sitting at 114 2/3 innings, the biggest workload in his career thus far. So when Herz was pulled at just 87 pitches with a no-hitter intact, there weren’t any hard feelings. At least, not yet.

“That day will come,” Herz said about being trusted to throw 100-plus pitches in the future. “There’s no need to rush it. It’ll come when it comes.”