ATLANTA — Fortunes never change more quickly than they do in October.

“We’re tired,” Chris Taylor, a utility player for the Los Angeles Dodgers, acknowledged as Sunday slipped into Monday and the Dodgers trudged toward their charter flight out of Georgia looking forward to Monday’s off day. “We’re ready to get home.”

Atlanta hastened the Dodgers’ readiness with timely hitting and clutch pitching over the first two games of this National League Championship Series, neither of which the Dodgers could muster.

Atlanta, champions of the N.L. East, won Game 2 just like they won Game 1, with a bottom-of-the-ninth-inning hit and a mad dash home. This time, it was Dansby Swanson racing in from second base after Eddie Rosario tattooed a 105-mile-per-hour screamer up the middle that one-hopped off Corey Seager’s glove behind second base to give Atlanta a 5-4 win.

Players spilled out of the dugout and mobbed Rosario, just as they had Austin Riley 24 hours earlier when Riley singled for the first game-winning hit of his major league career.

The Dodgers arrived here three days ago after winning the N.L. wild-card game and then sending the team with baseball’s best record this year, San Francisco, packing in a division series.

Now?

“My arm was dead,” said starter Max Scherzer, who was making his third appearance in seven days and fourth in 12 days. “I could tell when I was warming up that it was still tired.”

Two batters into the game, Dodgers shortstop Corey Seager smashed a two-run homer. But in the fourth, Scherzer surrendered a monstrous, 454-foot, two-run blast to former Dodger Joc Pederson to give the lead back and make it 2-2.

The Dodgers seized another two-run lead in the seventh thanks to Chris Taylor’s double, but then opted to bring 20-game winner Julio Urias in from the bullpen to start the eighth inning instead of handing things over to a conventional reliever. Like Scherzer before him, Urias did not have his best stuff and Atlanta ambushed him for three hits, making it 4-4 on Riley’s double over Mookie Betts’s head that allowed Ozzie Albies to score from first base.

“Julio, in my opinion, was the best option we had,” said Manager Dave Roberts of using Urias in that situation rather than Brusdar Graterol, lefty Justin Bruihl and closer Kenley Jansen. He added that Urias should be fine to start Game 5 on Wednesday, should the game be necessary, despite Sunday’s pummeling in which he surrendered hits to half of the batters faced.

Suddenly, shockingly, the Dodgers are in deep trouble. They went 1 for 10 with runners in scoring position Sunday and 2 for 18 in Games 1 and 2 combined. Their pitching is a mess. They left town shellshocked.

“It’s not an excuse, you don’t get breaks during the season, but we haven’t had a break, really,” said Mookie Betts as he walked down the quiet concourse toward the team bus. “A day off. We’ve constantly been playing catch-up. But it is what it is. It’s what we signed up for.”

It would be wrong, Betts said, to call what happened in Atlanta a letdown.

“You’ve got to give credit to them boys over there,” he said. “They’re playing really well. We’re not. We can’t call it a letdown. We’ve got to hit, man. That’s all it really is.”

Betts talked about how good Atlanta is and, despite the fact that the Dodgers won four of six games against them this summer, that notion is nothing he needs to sell to his teammates. Part of what has made these first two games so surprising is that this is a rematch of last year’s N.L.C.S. in which Atlanta took a three-games-to-one lead. The Dodgers were able to climb out of that hole with three consecutive wins.

That memory remained fresh when Los Angeles arrived at Truist Field on Saturday. But on their flight home, especially given the state of their pitching staff and the fact that Justin Turner, the heartbeat of their clubhouse, was a late Game 2 scratch with what the team said was a sore neck, the Dodgers had to be wondering whether they have another comeback left in them.

Taylor said that Seager makes the play on Rosario’s ball nine out of 10 times even given the sink and spin on it.

“Nine out of 10 times, but there’s always that one,” Betts said. “It’s a tough play. It’s a tough play for anyone. It’s not Seager’s fault.”

It had looked like Atlanta had neutralized the Los Angeles threat when, two batters before the walk-off, Swanson had pushed a bunt toward the mound with a runner on first. Graterol gloved it, wheeled and fired to second for the force. But that throw bounced and Seager made a sensational pick to prevent the ball from bouncing into center field. He got the out.

“They just apply pressure on us over and over again,” Betts said, “and we finally cracked.”

It didn’t have to be that way for the Dodgers. Not only did Betts start the game with a single and Seager followed with the homer, but Atlanta starter Ian Anderson was wobbly, throwing only 11 strikes in his first 26 pitches. The Dodgers, with three more base runners in the first, had a chance to pour it on and couldn’t do it.

“I think it’s everything, physically and mentally draining,” Taylor said. “These games, they’re four, five hours long. The level of focus is a little different than regular-season games. It’s definitely exhausting, but that’s what you expect. Everybody on this team has experience with it.”

He talked about regrouping on Monday and getting back to it in Game 3 Tuesday. Walker Buehler, one of the Dodgers’ aces, is rested and ready.

“We definitely believe we can win with him,” said Scherzer, who lasted only four and a third innings and 79 pitches on Sunday.

It is October, and fortunes change quickly. For the Dodgers, they’d better. Because the days are running short.