BALTIMORE -AP- David Ortiz broke open a tight game with a three-run homer in the seventh inning, and the Boston Red Sox beat the Baltimore Orioles 5-2 Tuesday night for their sixth straight victory.Jackie Bradley Jr. also homered for the Red Sox, who stretched their lead over Baltimore in the AL East to five games. After sweeping four games from the Yankees, Boston has won the first two of this pivotal four-game series. The Red Sox are 11-3 in their last 14 games and a major league-best 13-5 in September.Trey Mancini homered in his major league debut with the Orioles, who began the day tied with Toronto for the two AL wild cards.The Red Sox led 2-1 in the seventh when Marco Hernandez and Mookie Betts singled off Kevin Gausman (8-11). One out later, Ortiz hit a 1-2 pitch far over the center-field wall.Playing in his final season, the 40-year-old Ortiz has 36 home runs and 121 RBI. Big Papi has hit eight home runs against the Orioles this season and 54 for his career.Betts also extended his run of success against Baltimore, going 3 for 5 and scoring twice. He is 16 for 31 at Camden Yards and has scored 16 runs in eight games.Eduardo Rodriguez (3-7) allowed two runs and four hits in 6 1/3 innings for Boston, his first win in 11 starts since July 16.Craig Kimbrel worked the ninth for his 28th save.After giving up four hits in eight scoreless innings last week at Boston, Gausman yielded five runs and 10 hits in 6 1/3 innings.Boston went up 1-0 in the third when Betts singled and scored on a grounder by Hanley Ramirez. Bradley hit his 26th homer in the fourth.Rodriguez retired his first 11 batters and held Baltimore without a hit until Mancini connected with two outs in the fifth. The rookie sprinted around the bases, taking about half the time Ortiz did during his home run trot in the seventh.