Ramirez hit his 40th homer and drove in three runs to back a strong pitching performance by Bronson Arroyo, and Boston took advantage of a key error by Miguel Tejada to hand the Baltimore Orioles their sixth consecutive loss, 6-3 on Friday night.
Edgar Renteria had two hits and scored three runs for the Red Sox, who remained one game behind the first-place New York Yankees in the AL East with nine games to go. New York beat Toronto 5-0.
Ramirez singled in a run in the first inning and hit a two-run homer in the seventh. Boston's cleanup hitter has four home runs in his last three games and seven in his last 13 after going 17 games without connecting.
"It means we have one of the most dangerous hitters in the game hitting back-to-back with David (Ortiz)," Red Sox manager Terry Francona said. "When Manny gets hot, he's not going to hit singles. We hope he hits a bunch of homers."
It is Ramirez's third 40-homer season with Boston, tying the club record set by Carl Yastrzemski.
Arroyo (14-9) overcame a sluggish start to improve to 4-0 in his last five starts, allowing three runs and seven hits in seven-plus innings. He's 7-0 in September since joining the Red Sox last season.
"Whatever he did, he found himself, because early he didn't have his good stuff," Francona said.
After allowing three runs, Arroyo retired 10 in a row before giving up a leadoff walk in the seventh.
"I got some easy outs and some quick innings," he said.
Mike Timlin, the fourth Boston pitcher, worked the ninth for his 10th save. Timlin, who blew a late lead at Tampa Bay on Wednesday, has inherited the closer's role from Keith Foulke, who is out for the season with two ailing knees.
Jay Gibbons drove in two runs for the Orioles, who were coming off a four-game sweep at New York. Baltimore managed just one hit after the fourth inning after building a 3-1 lead in the third.
"I was really excited when we came out of the chute. That was as much energy as I've seen," interim manager Sam Perlozzo said. "We just couldn't muster anything else after that."
Before the game, the Orioles told first baseman Rafael Palmeiro that his season is over. Palmeiro, who was to return from a rehabilitation stint at home, has been a huge distraction to the team since his Aug. 1-10 suspension for steroid use.
Boston scored three unearned runs off Daniel Cabrera (10-12) in the fifth to take a 4-3 lead. With two on and two outs, Ramirez hit a bouncer to deep shortstop. Tejada, who faced questions this week about a vitamin he gave Palmeiro, made a high and wide throw to first that allowed a run to score. Trot Nixon followed with a two-run double to right-center.
Although Nixon's hit gave Boston the lead for good, the key to the inning was the grounder by Ramirez.
"Daniel got the ball that he needed to get on a great hitter, and we just didn't make the play," Perlozzo said. "It cost us."
Ramirez made it 6-3 in the seventh with a shot to center off Eric DuBose on a 3-2 pitch after Renteria hit a leadoff single.
"Beautiful swing," Francona said. "I will always take being up three as opposed to one."
Boston used an RBI single by Ramirez to go up 1-0 in the first inning, but Baltimore scored twice in the bottom half. After Tejada and Gibbons hit run-scoring singles, Arroyo averted further damage by retiring B.J. Surhoff and Chris Gomez with the bases loaded.
"I don't get Surhoff out," Arroyo said, "(Reliever Leonard) Dinardo's in there and I'm out."
Successive doubles by Tejada and Gibbons made it 3-1 in the third, but the Orioles did little else offensively in their eighth loss in nine games.
"I'm not tickled to death," Perlozzo said. "I don't like losing, they don't like losing. We've only got one choice, and that's to keep playing hard."
- Tejada's third-inning double was his 50th of the season, tying the club record set last year by Brian Roberts.
- The victory moved Arroyo over .500 for the first time in his career (33-32).
- The game drew a crowd of 46,850, the Orioles' 13th sellout. A majority of the fans cheered for Boston.
- The Red Sox improved to 8-8 against Baltimore this season.