The Braves made upgrades to bolster their bullpen at the trade deadline with an eye on October, hoping to turn a weakness into a strength. Instead, their bullpen loomed large again, and as a result, they trail the NLDS after one game.

Holding a 3-1 lead entering the eighth inning, the Braves surrendered six runs and lost Game 1 to the Cardinals 7-6. It was their ninth consecutive Game 1 loss and flipped home-field advantage in favor of St. Louis.

It also further ups the stakes of Game 2. The Braves can’t afford to lose another home game before the series shifts to the Midwest.

“That hurts,” first baseman Freddie Freeman said. “We had a couple-run lead heading into the final six outs. The way we played all season, you can almost expect to win those games. You give up that kind of lead, it’s tough to swallow.”

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The unraveling began when reliever Chris Martin came on to warm up for the eighth but quickly exited because of a left oblique injury. Enter Luke Jackson, who surrendered a homer to the first hitter he faced, Paul Goldschmidt, that cut the lead to one.

Martin, meanwhile, will be replaced on the NLDS roster. The Braves will announce their move Friday.

Jackson ran into more trouble after retiring Marcell Ozuna and Yadier Molina. Paul DeJong and Kolten Wong tagged him for back-to-back singles. Mark Melancon came on for the potential four-out save.

A seven-pitch at-bat ended with Matt Carpenter dropping a single to left that scored the tying run. Adam Duvall – who replaced Nick Markakis – threw Wong out at home to momentarily preserve the tie.

Melancon recorded an out to begin the ninth before the disaster commenced. St. Louis scored four runs in the inning. Their rally began with back-to-back singles by Dexter Fowler and Tommy Edman. Melancon pitched around Goldschmidt, loading the bases.

Ozuna, in an 0-2 count, ripped a curveball past third base for a two-run double that put the Cardinals in front. Melancon intentionally walked Molina and struck out DeJong.

Still in the game, Melancon was struck one more time. Wong shot a ball past first base – another liner – that scored two more. Melancon was finally lifted, but the collapse was complete.

“Those pitches have to be better,” Melancon said. “The bullpen did good, in my opinion. It was me that did bad. I’m going to own that one. That’s on me. I feel like I gave that game away.”

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The Braves, up two runs entering the eighth, were down four when they came to bat in the ninth. Georgia has seen its share of brutal finishes, and this result falls right in line. The home-field advantage the Braves worked so hard to earn in the regular season is gone.

Home-field advantage: Cardinals. Series advantage: Cardinals. And it largely was because of a unit, the bullpen, that the Braves hoped they’d fixed. Instead, those past woes - which had felt mitigated - extended into the postseason to a significant degree.

It wasn’t a quiet finish from the Braves, who scored three runs in the bottom of the ninth. Billy Hamilton drew a lead-off walk and Ronald Acuna, who had a tremendous game sans his lack of hustle on a would-be double, homered to make it 7-5. Freeman hit a solo shot to bring the Braves within a run, but Carlos Martinez retired Josh Donaldson and Nick Markakis to end it.

“You have to put it behind you,” manager Brian Snitker said. “Tomorrow's a new day. We're going to come out, do everything we can to win tomorrow. I know it's the postseason, but again it's baseball. We've been through this a lot. We've lost a lot of tough games, came back and rallied and had good runs and we'll have to do the same tomorrow.”

Another subplot: Acuna’s stroll out of the box on what he thought was a homer. It wound up a long single off the wall, bringing back memories of the day he was benched in August against the Dodgers for prematurely admiring a long hit.

Acuna, who advanced to second on Albies’ grounder, was caught in an inning-ending double play when Donaldson lined out. It’s difficult to project how different the inning could’ve been had he hit a double rather than single, but his teammates made it clear the admiring must stop.

“It’s a big deal,” Albies said. “He knows he needs to do better there. ... We have the chance for (a big) inning. He probably scores that inning if he’s at second base.”

Freeman added: “It’s frustrating. You have that conversation once and you’re beating a dead horse after you keep having that same conversation over and over again. You have to know that’s a mistake. It can’t happen in the playoffs. It can’t happen in the regular season. Unfortunately that happened tonight.”

Snitker alluded to the thought of benching Acuna had the team not been short on the bench. Acuna admitted he’d have handled the play differently.

“I always try to give my best effort,” he said via team interpreter Franco Garcia. “Those are the things that get away from me. I’d have a double if I could take things back.”

While Acuna will remain a hot topic of conversation, he was far from the reason the team dropped Game 1. He had three hits, falling a triple shy of the cycle. At 21 years and 289 days old, he became the third youngest to post three hits and a homer in a postseason game (after Andruw Jones and Carlos Correa).

Dallas Keuchel went 4-2/3 innings, allowing only a run but striking out none. He fell well short of his consistent goal of seven innings but he did his job: He kept the game within reach.

To open the game, the ground-ball specialist retired the Cardinals 1-2-3 without their hitters clearing the infield. He allowed a two-out single in the second in an otherwise two clean frames.

The third and fourth innings illustrated why the Braves trusted Keuchel to start Game 1. Twice he ran into trouble through a double and walk. Twice he induced a 5-3 double play – with Donaldson making a pair of nice plays at third – to quiet the noise.

St. Louis finally broke through in Keuchel’s final inning. Harrison Bader singled with one down and advanced on pitcher Miles Mikolas’ bunt. Bader stole third - a play in which Keuchel took full responsibility - and scored on Atlanta native Dexter Fowler’s grounder.

Edman followed with a double that ended Keuchel’s outing at 4-2/3 innings. Darren O’Day, who made the postseason roster after an encouraging September, got Goldschmidt to line out to Dansby Swanson to end the fifth.

Keuchel would be available for a potential Game 4 or 5, should the series reach that point.

The Braves had taken their two-run lead in the sixth. Then a 1-1 tie, Donaldson was hit in the hand by a pitch, giving the Braves a base runner with one down against Cardinals reliever Tyler Webb, who spelled starter Mikolas. Markakis followed with a double that just cleared first baseman Goldschmidt’s head.

Webb intentionally walked Duvall to load the bases. Giovanny Gallegos entered for Webb and struck out Francisco Cervelli, putting the pressure on Swanson.

The Battery Atlanta was packed Thursday with baseball fans, before the first game of the National League Division Series between Atlanta Braves and St. Louis Cardinals at SunTrust Park. Watch as fans declare their fandom for the Braves and one fan offers up prayers for its star players. (Video by Tyson Horne, Kelly Audette, and Ryon Horne)

Swanson drew a 3-0 count before a questionable strike extended the at-bat. On the next pitch, Swanson hit a one-hopper to third, where rookie Edman struggled to field the ball.

Shortstop DeJong caught the ball off a ricochet and fired an errant throw into second. Wong couldn’t reel it in, allowing a second run to score. A 1-1 tight game flipped to a 3-1 lead in the Braves’ favor, positioning them for what they hoped would be their first Game 1 win at home since 1999.

The Braves and Cardinals play Game 2 at 4:37 p.m. Friday at SunTrust Park. Mike Foltynewicz, whose second-half revival re-earned his spot in the Braves’ rotation, faces an even hotter Jack Flaherty, who posted a 0.91 ERA in the second half to lead the majors.

“That was a game that should’ve been ours,” Freeman said. “Forget about this and build off that bottom of the ninth. We had a lot of energy, our guys swung the bats nicely there. We’re starting Foltynewicz and they’re starting their best (Friday), so we’ve got our hands full. But this is the playoffs, everybody is going to be good. We know it’s a must win. We have to win this game tomorrow.”