PHILADELPHIA – Five days after Ervin Santana’s frustrations boiled over in a postgame interview in which he spoke of added pressure from pitching with poor run support, the Braves staked him to a 4-0 lead in the first four innings Friday against the Phillies.

And he proceeded to give it all back.

After the Phillies scored a run in the fifth and three runs on a two-out rally in the sixth, they took the lead with a run against reliever Jordan Walden in the seventh inning for a 5-4 win in a series opener between sub-.500 teams that are going home when the regular season ends Sunday.

“Four runs, with one of your best pitchers on the mound, should be enough,” said manager Fredi Gonzalez, whose Braves have lost 12 of 14 games. “But sometimes you find different ways to put yourself in a corner.”

The Braves have a majors-worst 5-18 record in one of the sorriest Septembers in franchise history.

“It’s very sad to finish the season this way, but it is what it is,” said Santana, who got no decision and finished 1-3 with a 6.51 ERA in five September starts. “I just want to thank the Braves for giving me the chance to play this year.”

There was some history made: B.J Upton struck out twice to give him a franchise-record 173 strikeouts, breaking the mark of 171 set by Dan Uggla last season.

Justin Upton reached the 100-RBI plateau for the first time in his career with an RBI single in the first inning that gave the Braves a 2-0 lead, and Chris Johnson’s two-run homer in the fourth pushed the margin to 4-0. It was the second time Atlanta scored more than three runs in its past 14 games, both of those outbursts in the past three nights.

“It’s very, very hard,” Santana said of blowing the lead. “Because when we get runs, we have to take advantage of it. My team, they do everything they can to score runs. So it’s not their fault.”

Santana, who had lost three consecutive starts before Friday, appeared poised to record his team-high 15th win after he pitched three perfect innings in the first four, and got out of a bases-loaded jam in the third inning.

But in the fifth he gave up a run on a fielder’s choice grounder, after allowing consecutive singles by Nos. 7-8 hitters Cody Asche and Freddy Galvis to start the inning.

Santana still had a 4-1 lead when he retired the first two batters in the sixth. And that’s when he ran into trouble and appeared to get flustered. He allowed four consecutive two-out hits including Asche’s RBI double and Galvis’ slow-rolling infield single, which Santana fielded near the third-base line before making an ill-advised toss from close range to catcher Christian Bethancourt as the base runner was passing between them.

That run reduced the lead to 4-3, and moments later it was tied after Santana bounced a wild pitch to Grady Sizemore that Bethancourt tried to backhand.

“I don’t think it was his composure,” Gonzalez said. “We gave him four runs. I think the rally started with two outs, nobody on. We just couldn’t get the third out. There was a couple of balls that looked like we got caught by surprise a little bit. The play at the plate on the ground ball, the topper on the third-base line. It looked like we just got surprised there. And the wild pitch that same inning. But I don’t think he lost his composure. I think he was upset. We let them back in the game, basically, in that inning.”

Santana was replaced after walking Sizemore, and rookie left-hander Chasen Shreve struck out Ben Revere to end the inning. But the damage had been done.

Santana gave up eight hits, four runs and two walks in 5 2/3 innings, the fourth time in his past five starts that he’s allowed at least four earned runs in six innings or fewer.

“Everything was good, I just got bad luck in the sixth inning,” said Santana, who was asked if he or Bethancourt could’ve done anything differently on the ground ball that Santana fielded near the line. “I think it was bad communication. Because I know I don’t have a chance at first base, and he was running right there. So I just tossed the ball to (Bethancourt). That was bad communication.”

An inning later, the Phillies scored the go-ahead run against Jordan Walden after he walked the leadoff batter, Carlos Ruiz. Ryan Howard doubled to put two runners in scoring position with one out, and Marlon Byrd’s ground out to second base gave the Phillies their fifth unanswered run and a 5-4 lead.

The Braves jumped on Phillies starter Jerome Williams in the first inning, when Phil Gosselin hit a leadoff single and Ramiro Pena doubled to put two runners in scoring position with none out.

Freddie Freeman grounded out to drive in a run, and Upton followed with a single to give him his first 100-RBI season. His career-best before this season was 88 RBIs with Arizona in 2011, when Upton also had a career-high 31 homers.

“I’ve never done it before, so that was cool,” he said of driving in 100. “Kind of sucks it was in a losing effort. We jumped out early and just didn’t get it done. So it’s kind of bittersweet.”

Santana struck out the first two batters in the third inning before giving up a single to the pitcher. Revere followed with another single and Carlos Ruiz walked to load the bases for Chase Utley, but Santana got out of the jam by inducing a ground out.

Johnson said Santana’s comments last week about poor run support weren’t an issue with him.

“It’s frustration (on Santana’s part),” Johnson said. “We all say things that we want to take back, or we’re frustrated, or it came out wrong. We’ve all made mistakes. I’m not one to judge, that’s for sure.”