BOSTON (AP) -- The Baltimore Orioles patiently came back from three different deficits then took their first lead when it mattered most.
The Orioles scored twice in the top of the 13th inning to outlast the Boston Red Sox 6-4 on Friday night.
Chris Davis drove in the go-ahead run with a single in the 13th, Mark Reynolds added a sacrifice fly and Jim Johnson put Boston down in order to end the game after 4 hours and 37 minutes.
Five Baltimore relievers combined to shut out the Red Sox once the bullpen took over for starter Wei-Yin Chen, who was pulled after reaching 100 pitches in just five innings.
"Everybody's contributing," said Reynolds, who hit his first homer of the season in the third. "It's just fun to play behind these guys. They throw strikes and keep us in games. That's all you can ask for."
The Orioles overcame three errors and a passed ball in the first two innings to win for the ninth time in 11 games.
Troy Patton (1-0) pitched two scoreless innings and Johnson picked up his eighth save.
Baltimore's five relievers allowed a total of three hits.
"As a defense that's all you ask for. It's a pitching staff that's going to go after the hitters and let us work," center fielder Adam Jones said. "The starting pitching has been outstanding. The bullpen, if there's a word better than outstanding, that's what they've been."
Franklin Morales (0-1) allowed two hits in 2-3 of an inning in Boston's eighth loss in its last nine home games.
"Everyone wants to play well at home, but we haven't. We've got to figure out how to do that," said Dustin Pedroia , who was 2 for 5 and scored a run for Boston. "We just couldn't find a way to score a run there when we needed to. It's tough."
Matt Wieters hit a one-out single off Morales in the top of the 13th and Wilson Betemit walked before Davis singled to right. Boston manager Bobby Valentine then brought in reliever Scott Atchison , who allowed Reynolds' sac fly to center.
Adrian Gonzalez had three hits for the Red Sox, who took three different leads but couldn't hang on to any of them.
The Red Sox had a chance to pull ahead in the bottom of the eighth when David Ortiz led off with a walk, but he got caught going too far on a line drive by Cody Ross . Shortstop J.J. Hardy made a diving grab then from his knees threw a strike to first in time to double up Ortiz.
"That's first and second with no outs. I would say that was a very big play in the game," Boston manager Bobby Valentine said. "That looked like it was by him when he caught it, David was kind of holding up."
Boston's Jon Lester lasted only slightly longer than Chen, going six innings before Vicente Padilla started the seventh with the Red Sox holding a 4-3 lead. That ended quickly when Baltimore loaded the bases with nobody out. Hardy grounded into a double play, allowing Reynolds to score - snapping a streak of 11 straight scoreless innings by Boston relievers over the last three games.
Will Middlebrooks , playing in just his second major league game, hustled for a double to lead off the fifth and scored on Pedroia's single for a 4-3 Boston lead.
"I just think everybody knows when it's their turn," Baltimore manager Buck Showalter said. "So far we're going to be able to pass the load around, and when it's their time to contribute, it bodes well for their health and the rest factor."
The Orioles had three errors before the second inning was over, then a passed ball by catcher Ronny Paulino allowed Ross to score and put Boston up 1-0.
Reynolds snapped an 0-for-13 skid with a leadoff homer over the Green Monster in the third to tie it 1-all, then Boston took the lead right back with a pair of runs in the third.
NOTES: RHP Aaron Cook , signed by Boston as a free agent in January, is scheduled to make his Red Sox debut Saturday after going 3-0 for Triple-A Pawtucket. Cook will start in place of Josh Beckett , who has had some stiffness after his last two starts. ... Reynolds' homer in the third was his first of the season. He went without a home run in April for the first time in his career. ... Ross lost his grip while striking out in the fifth and the bat sailed high over Baltimore's dugout and - fortunately - landed in an aisle without hitting anybody. ... Lester was 14-0 with a 2.36 ERA in 18 career starts against Baltimore entering the game. ... Boston RHP Daisuke Matsuzaka was scheduled to make his third rehab start Friday night for Triple-A Pawtucket, but has a problem with his neck. He is tentatively scheduled to start Monday against Rochester. ... The Orioles placed OF Nolan Reimold on the 15-day disabled list with a herniated disc and recalled C Luis Exposito from Triple-A Norfolk. ... Joe Torre , MLB's executive vice president for baseball operations, changed an official scorer's decision and gave Nick Johnson an additional double in Tuesday night's game against the Yankees. Torre took an error away from left fielder Eduardo Nunez , who allowed the ball to fall. That made both runs earned off Boone Logan .