AP photo by Ben Margot / The Atlanta Braves' Ronald Acuna Jr., center, speaks with a trainer as manager Brian Snitker, left, looks on after Acuna was hit by a pitch thrown by Arizona Diamondbacks starter Zac Gallen in the first game of Sunday's doubleheader in Atlanta.

ATLANTA — Madison Bumgarner definitely had the stuff of which no-hitters are made, even if the Major League Baseball record book said he didn't have an actual no-hitter.

Bumgarner threw a seven-inning no-hitter, an achievement that won't officially count but completed a dominant afternoon of Arizona Diamondbacks pitching for a 7-0 win over the Atlanta Braves and a doubleheader sweep Sunday.

Could he have kept the magic going for a nine-inning game?

"I don't know. There's too many variables," Bumgarner said. "If it worked for seven, it's hard to imagine it not working for two more."

After Zac Gallen tossed a one-hitter to win the opener 5-0, Bumgarner did even better.

The 31-year-old four-time All-Star struck out seven batters, and the only Atlanta baserunner in the second game resulted from shortstop Nick Ahmed's throwing error in the second inning.

Bumgarner casually shook hands with catcher Carson Kelly after Marcell Ozuna lined out to end it, and then the rest of the Diamondbacks joined in and the celebration livened up around the mound.

"I like to keep it pretty low key," the stoic left-hander said. "They definitely didn't, which that's fine and I appreciate that, too. It's pretty special for all of us, and like I said, I'm just blessed and fortunate to be able to do that and be a part of this."

Commissioner Rob Manfred and MLB switched to seven-inning doubleheaders last year during the coronavirus pandemic, but MLB's eight-man committee on statistical accuracy decided in 1991 that a no-hitter was a game of nine or more innings that ended with no hits.

"It feels good. I just want to say two things before I go celebrate with the guys," Bumgarner said on a TV interview after the game. "I want to thank these shadows in Atlanta. They helped me out a good bit. That was awesome. And I want to thank Rob Manfred for making these seven-inning games."

There have already been two official no-hitters this season. Joe Musgrove pitched the first in the history of the San Diego Padres in an April 9 road game against the Texas Rangers. Carlos Rodón of the Chicago White Sox held the Cleveland Indians without a hit — and took a perfect game into the ninth inning — on April 14.

Atlanta's only hit Sunday was by reigning National League MVP Freddie Freeman, who lined a clean single to right-center field off Gallen with one out in the sixth of the opener.

Despite the games going just seven innings, Bumgarner and Gallen are officially credited with shutouts. That made Arizona the first team to throw a pair of complete-game shutouts in a doubleheader since Reggie Cleveland and Don Aase for the Boston Red Sox against the host Toronto Blue Jays on Sept. 5, 1977.

Bumgarner (2-2) struck out Ronald Acuña Jr. to begin the seventh, then retired Freeman on a popup that Ahmed went a long way to get. Ozuna lined an easy fly to right fielder Josh Rojas for the final out, and Arizona completed a 10-game road trip 7-3.

The 2014 World Series MVP with the San Francisco Giants, Bumgarner retired the last 17 batters after Ozzie Albies reached on Ahmed's error leading off the second.

The Diamondbacks scored five runs in the first off Drew Smyly (0-1). Pavin Smith and David Peralta homered during the outburst, and Eduardo Escobar added his seventh homer of the season to make it 6-0 in the third.

Smyly, who came off the injured list Saturday after missing six games with left elbow inflammation, went four innings.

In the first game, Gallen (1-0) struck out six, walked two and hit a batter.

"It wouldn't have counted (as a no-hitter), so that makes me feel better that it wasn't actually a no-hitter anyway," the 29-year-old right-hander said. "The complete-game shutout, I guess, works. That's fine. We won. It really doesn't matter. That's the most important part."

Arizona's Stephen Vogt and Kole Calhoun homered off Bryse Wilson (1-1) in the opener.

Atlanta manager Brian Snitker said he couldn't fully explain why the Braves struggled so much at the plate all afternoon, but he's grateful his club, despite being 9-12 after winning the division for three straight years, hasn't fallen far back in the NL East.

"Nobody's running away with anything, and that's a good thing," Snitker said. "We're going to hit a stride here at some point and time. It's good that we're staying right there. We have five more months to go. It's a long time to do some really good things."