ATLANTA — The Los Angeles Dodgers reached the National League Championship Series with a final, bitterly contested pitch on Thursday night in San Francisco.

Its last-pitch luck — or sorcery or absurdity or whatever your baseball loyalties lead you to call it — did not last.

Instead, with Game 1 of the N.L.C.S. tied in the ninth inning on Saturday, Atlanta’s Austin Riley lifted Blake Treinen’s offering into left field, transforming a slider into a starting gun for Ozzie Albies. Racing from second base, which he had stolen moments earlier, Albies crossed home plate to give Atlanta a win, 3-2, in the best-of-seven series.

It was the franchise’s first N.L.C.S. win here since 1999.

“I was just trying to get a base hit and luckily it came through,” said Riley, whose home run had devastated the Dodgers in Game 1 of last season’s N.L.C.S.

“You dream of that as a little kid,” he said on Saturday.

The theatrics were a thrilling coda to a game that featured two of baseball’s most swaggering offenses but proved to be more of a defensive showcase. There were running catches, and also a rundown. The teams combined for 21 strikeouts. In his sixth career postseason start, Atlanta’s Max Fried went six innings and allowed two runs on eight hits.

“They hit some balls hard and were looking for pitches in certain areas and that’s what good teams do,” Fried said. “It’s a really tough game, so to be able to come out there and keep us in the game was basically my objective today and I was happy to be able to do that.”

The Dodgers weighed using Max Scherzer, the three-time Cy Young Award winner, to start the series against Atlanta. But after Scherzer earned the first save of his professional career on Thursday night, when he pitched the ninth in San Francisco, he and Manager Dave Roberts decided that he would start for Los Angeles in Game 2, which will be played in Atlanta on Sunday.

Instead, the Dodgers named Corey Knebel as its “opener” for Game 1. Seven other Los Angeles pitchers, only one of whom worked longer than 15 pitches, followed.

“We just ran into a tough pitcher tonight,” Chris Taylor, the Los Angeles center fielder who got caught up in the rundown in the ninth inning, said of Fried. “He’s been the best pitcher in the league the second half. We were able to get a couple runs across on him. It was one of those games. We squandered a couple of opportunities and they took advantage.”

Both teams threatened in the first. In the top half of the inning, Corey Seager sent a slider past a diving Albies into right-center for a double. But Fried, who had earned two outs on four pitches to start his night, outlasted Justin Turner in a seven-pitch at-bat with a strikeout on a checked swing.

Then came Atlanta’s turn. Eddie Rosario, in the leadoff spot instead of Jorge Soler, who tested positive for the coronavirus during the division series, singled down the first base line off Knebel. Rosario stole second and then, helped by a ground ball by Albies, moved to third. Riley struck out after four pitches. But the very first one, a 97-mile-an-hour fastball, was wild and bounced behind home plate. Rosario slid in from third to score Saturday’s first run.

Atlanta’s lead did not linger. In the second, Fried again swiftly got two outs, but A.J. Pollock, who entered Saturday’s game with a .183 batting average in his postseason career, swung at a curveball and drove it deep into right. Taylor, a hero of this Los Angeles postseason for his walk-off home run in the wild-card game against St. Louis, reached a full count before his single into left gave Pollock enough time to score.

Will Smith, the Los Angeles catcher, broke the tie after he stood in the batter’s box as the fourth inning’s first hitter. He quickly took called strikes on a pair of curveballs before Fried went to his fastball. Smith sent it surging 416 feet into the left-field stands for a home run, his third of the postseason.

It was Los Angeles’s turn for a lead to vanish fast. With one out in the fourth, Tony Gonsolin entered as the Dodgers’ fourth pitcher of the evening. He got the inning’s second out with a fly ball from Albies. Riley, Atlanta’s cleanup hitter, lurked around the on-deck circle, though. As he walked to the plate, a smattering of chanters demanded that he win the league’s Most Valuable Player Award.

Riley missed a slider. He took another, that one at the same speed, 87 miles an hour, as the first but just a bit farther off the plate. A fastball came next, followed by a crack, a rising roar and a solo home run to left.

The scoreboard toggling stopped, the latest tie stretching half of the game.

The Atlanta lineup in the ninth inning, though, promised perils. There was Freddie Freeman, the first baseman whose eighth-inning home run on Tuesday gave Atlanta just enough to beat the Brewers in Game 4 of their division series. He found no such magic on Saturday, when he became the last of 14 Atlanta strikeouts.

Albies, who levitated in the sixth inning for a catch to extinguish one of Los Angeles’s most menacing scoring opportunities, swung at the first pitch he saw from Treinen. The ball lobbed toward the outfield, near the etching in the grass honoring the Atlanta slugger Hank Aaron, who died in January.

A trio of Dodgers closed in. The ball dropped onto the field. The winning run was on the basepaths with one out.

The M.V.P. cheers returned as Riley came to the plate. Albies was off running soon enough.

Hours after Richard G. Sneed, the principal chief of the Eastern Band of Cherokee Indians, cried “play ball” before a sold-out Truist Park, the chop chant swelled. Atlanta fans rhythmically swung their right arms. Treinen looked toward the plate and fired his pitch on an 0-1 count.

Riley swung at the pitch, on the bottom half of the strike zone. The ball slammed into the outfield, hopping toward the left-field corner. Albies, helmet off and arm raised in celebration, dashed across home plate. The entire sequence took perhaps seven seconds.

Albies said afterward he had never doubted that Riley would come through. Last year, after all, he had faced Treinen in a tied Game 1 of the N.L.C.S. His home run in that game’s ninth inning started a four-run rally for Atlanta, which was playing as the visiting team on a neutral field in Texas because of the coronavirus pandemic.

That night, Atlanta proved to need only his swing to secure a win late — much as it went again on Saturday night in Georgia.

Scott Miller contributed reporting.