ATLANTA -- One night after staging a thrilling ninth-inning comeback, the Braves bid adieu to their season-best winning streak and gained more reason to believe they will eventually need to acquire a proven closer.  

Luke Jackson has spent the past couple months constructing a feel-good story and proving that he has the ability to be a quality Major League reliever. It can be argued the bad-luck bug that has plagued him a little too frequently the past few weeks bit him again when he was unable to protect a one-run ninth-inning lead in Saturday night’s 6-5 loss to the Phillies at SunTrust Park.  

But as the Braves attempt to maintain their status atop the National League East standings and face the fact their potent offense can’t protect the pitching staff on a nightly basis, they have to realize they need something more reliable than a closer who has now allowed a run in seven of his past 11 appearances.  

“He’s good,” Braves catcher Tyler Flowers said. “He’s just in a tough stretch right now.”

Jackson’s rough stretch was extended when Cesar Hernandez’s opposite-field, two-run single through the unguarded side of a shaded infield gave the second-place Phillies a ninth-inning lead they would not relinquish against the first-place Braves, who found themselves with just a 1 1/2-game division lead after ending their eight-game winning streak.

“We’re going to play a lot of close games, especially with a team like that over there,” Braves third baseman Josh Donaldson said. “They’re a good opponent. Sometimes, we’ll get the best of them, and sometimes, they’ll get the best of us. At the end of the day, we’ve got to turn the page.”

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This had the makings to be yet another potentially key day for the Braves. They were three outs away from gaining a 3 1/2-game division lead courtesy of a win that would have been fueled by the encouraging performance of Donaldson, who highlighted his three-hit day by hitting a monstrous go-ahead three-run homer off Aaron Nola’s changeup in the fifth.

Donaldson’s 432-foot homer that had a 111.6 mph exit velocity -- the sixth-hardest homer he’s recorded since Statcast began tracking in 2015 -- might be a sign the ‘15 American League Most Valuable Player Award winner is ready to get on a roll. But the resulting one-run advantage was not enough for Jackson, who has now blown six of his 16 save opportunities.

After Scott Kingery began the ninth by lining a slider to left field for a leadoff single, Jackson then made an errant throw to first base on Sean Rodríguez’s sacrifice bunt attempt. This set the stage for Hernandez, who slapped a loopy outside slider the other way to give the Phillies the lead.

“He was kind of his own worst enemy there because you don’t know what happens if he gets an out,” manager Brian Snitker said. “It’s just the life of a closer or the guy pitching in the ninth inning. You’ve got to have a short memory.”

There’s no denying the capabilities of Jackson, who possesses a fastball that sits slightly above 95 mph and a slider that rests in the upper 80s. The 27-year-old right-hander was one of the last relievers to be given an Opening Day roster spot, but he became the closer when Arodys Vizcaíno underwent season-ending surgery, and A.J. Minter faltered and was sent to Triple-A Gwinnett.

But he’s not the same guy who posted a 0.42 ERA while limiting opponents to a .197 batting average and .247 on-base percentage over 19 appearances from April 31-May 17. His heavy reliance on the slider aided that successful run. But opponents have seemingly been sitting on what has been a less-effective slider while Jackson has posted a 4.97 ERA and allowed opponents to hit .321 with a .356 OBP over his past 11 appearances.  

“He relies on his breaking ball a fair bit, but he’s got some fastball velocity to go with it and decent command,” Flowers said. “That’s kind of the challenge. Everybody knows you have a good breaking ball. So, they’ve got two choices: to hit it or look for the fastball. So it’s our job to execute breaking balls when we think they’re looking for them and try to keep them off balance with fastballs up in the zone.”  

Jackson certainly has the stuff and mental fortitude to bounce back from this rough stretch. But in the meantime, the Braves may want to once again begin testing Minter in the closer’s role. The young southpaw has been reenergized since returning from his demotion earlier this week. He notched the second of his two strikeouts on Saturday by ending the seventh with Bryce Harper swinging through a 97.5 mph fastball. 

“Today was probably the best I’ve seen him all year,” Snitker said. “He looked like his old self. The velocity ticked up, and the cutter was good. That’s the best he’s looked since we started in February, which is really encouraging.”