BALTIMORE -AP- Rick Porcello pitched a four-hitter for his major league-high 21st victory, David Ortiz and Mookie Betts hit two-run homers and the Boston Red Sox beat the Baltimore Orioles 5-2 on Monday night to pad their lead in the AL East.Coming off a four-game sweep of the Yankees, Boston sustained its late-season surge in the opener of an important four-game series for both clubs. The Red Sox stand atop the division by a season-high four games. Adam Jones homered and Mark Trumbo picked up his 102nd RBI for the second-place Orioles, who started the day with a one-game lead over Toronto for the top AL wild card.Porcello (21-4) struck out seven and walked none in his third complete game of the year. Five days earlier against Baltimore, the right-hander gave up one run in eight innings but took the loss.Porcello has allowed three runs or fewer in 11 straight starts and is sure to receive strong consideration for the AL Cy Young Award after going 9-15 last year.Playing his final regular-season series in Baltimore, the 40-year-old Ortiz connected against rookie Dylan Bundy (9-6) with a man on in the fifth for a 5-1 lead. It was his 35th home run of the season and the 53rd of his career against the Orioles.Betts put Boston up 2-0 with his 31st homer in the third. It was his eighth home run in seven games at Camden Yards -- most in a season by a Red Sox in a visiting ballpark since Jimmie Foxx hit eight in St. Louis in 1939.Porcello retired the first 11 batters before hitting Manny Machado with a pitch in the fourth. Trumbo followed with an RBI double.The Red Sox responded with a three-run fifth. Dustin Pedroia snapped an 0-for-12 skid with a run-scoring single before Ortiz launched a 1-1 pitch over the 25-foot scoreboard in right field.Jones homered in the eighth, his 28th.