BOSTON — The Atlanta Braves loaded the bases with nobody out in the first and got just one run out of it.

It was an ominous start that quickly got worse in an 8-4 loss to the Boston Red Sox on Saturday night.

Atlanta took a 1-0 lead in the first, but Boston answered with two runs in the bottom half, added two more in the second while chasing starter Randall Delgado after 1 1/3 innings and kept the Braves out of reach the rest of the way.

“We should have gotten more out of the first than we did,” third baseman Chipper Jones said. “We really had a chance to kind of set the tone for the ballgame and have them play catch-up and hopefully give our young guy a little bit of breathing room.

“Unfortunately we only got the one and they come out of the top of the first really feeling good about things as opposed to being down two or three runs.”

Jones had an RBI double in the sixth that pulled Atlanta within 6-3. The Braves added another run in the seventh to cut it to 6-4, but Boston scored twice in the bottom of the seventh and held on to even the series at 1.

“We scored four different innings and they come back and scored three of those innings. You get a couple of shutdowns and it’s a different game,” Atlanta manager Fredi Gonzalez said. “We kept battling and we made it a game. They just kept adding on every time we scored.”

Will Middlebrooks had a solo homer among his three hits and drove in two runs and Franklin Morales gave Boston another decent start as the fill-in for Josh Beckett.

Dustin Pedroia added three hits, a walk and had two RBIs for Boston, which won for the eighth time in 10 games to ensure a winning interleague record for the eighth straight season. The Red Sox improved to 10-7 against NL opponents.

Morales (1-1) gave up three runs — two earned — and seven hits, striking out eight and walking one. He struck out a career-best nine in five innings last Sunday night against the Chicago Cubs, when he took Beckett’s turn in the rotation after the right-hander was placed on the 15-day disabled list with shoulder inflammation.

Delgado (4-8) was knocked out after retiring only four batters, giving up four runs and six hits.

“He just didn’t have location (Saturday),” Jones said. “When a young kid struggles with location, it snowballs on him fast.”

Michael Bourn had three singles, two stolen bases and two RBIs for the Braves, who lost for just the second time in their past nine road games.

Trailing 1-0 in the first, Boston scored two runs when Adrian Gonzalez had an RBI single and Middlebrooks followed with a run-scoring double off the Green Monster.

The Red Sox chased Delgado in the second and increased it to 4-1 on Pedroia’s two-run double to the gap in left-center. Cristhian Martinez relieved with the bases loaded and got Gonzalez to bounce into an inning-ending double play.

Middlebrooks hit Martinez’s first pitch of the third into the Monster seats, making it 5-1. It was the ninth homer of the season for the rookie third baseman, who has made it hard for manager Bobby Valentine to keep him out of the lineup.

Middlebrooks has gone 10-for-14 in his past five games with three homers, three doubles and nine RBIs, and is hitting .381 in his past 26 games.

Bourn’s RBI single cut it to 5-2 in the fifth, but Cody Ross’ RBI double restored Boston’s four-run lead in the bottom of the inning.

Atlanta cut it to 6-4 against Scott Atchison in the seventh, but Brian McCann lined into an inning-ending double play against Andrew Miller with runners on the corners.

In the seventh, Daniel Nava had a two-run single for Boston.

The Braves had taken a 1-0 lead in the first on McCann’s run-scoring infield hit. Morales then struck out the next two batters before getting Jones to line out.

NOTES: Braves RHP Jair Jurrjens was feeling fine a day after his first major league start since late April when he held the Red Sox to one run and three hits in 7 2/3 innings of a 4-1 win on Friday. He was sent to the minors to “strengthen his right knee” that caused him to miss all of last September. ... Neither team took batting practice on the field due to a strong line of thunderstorms that hit the area about 2½ hours before the start. ... Middlebrooks started for the third straight game, leaving Kevin Youkilis on the bench for the third in a row. “Difficult and stressful and all those things,” Valentine said of how the situation’s been to handle. Before the game Youkilis joked, “I’m not dead. I’m still here,” when asked to recall some of his memories in Boston. ... Pedroia was 0-for-11 coming into the game. ... Braves lefty Mike Minor (3-5) faces Aaron Cook (0-1) in the series finale today. Cook will replace Clay Buchholz, who was scratched due to an illness.