ST. PETERSBURG, Fla. -AP- With the complicated math of baseball in the wild-card era, players in the Boston clubhouse was unaware the Red Sox are playoff bound.Dustin Pedroia hit his fourth career grand slam to help Rick Porcello get his major league-leading 22nd win, and the Red Sox clinched a playoff berth by beating the Tampa Bay Rays 6-4 Saturday night for their 10th consecutive win.Boston maintained a 5 1/2-game lead over Toronto for the division title and ensured no worse than the AL's second wild card. While the Red Sox technically have a magic number of one, the Blue Jays and Baltimore Orioles play each other three times in the season's final week -- meaning only one of them can win match Boston's 91 wins.Among the other wild-card contenders, only Detroit can reach 91 victories."I haven't heard it," Red Sox manager John Farrell said moments after the game.Porcello was informed of the news by a reporter."Obviously, it's big," Porcello said. "It's the position that we wanted to be in coming into this last week of September. We definitely want the division going forward."Boston is on its longest September winning streak since an 11-game run in 1949.Pedroia stopped an 0-for-17 skid with a single in the sixth and gave Boston a 6-3 lead with a seventh-inning drive off Danny Farquhar."Everybody is obviously grinding," Pedroia said.Pedroia hit several foul balls, including one off his toe before going deep."You can see why he's as good as he is because he fought off some good pitches and got his pitch (a changeup) and crushed it," Farquhar said.Porcello (22-4) gave up three runs, eight hits and struck out nine over 6 1/3 innings. He just missed getting his 12th consecutive start of seven or more innings and three runs or fewer, which would have moved him past Cy Young (1904) and Pedro Martinez (2000) for the longest stretch during the same season in franchise history.Porcello is first Boston pitcher to have 22 wins since Martinez had 23 in his AL Cy Young Award winning season in 1999.Craig Kimbrel, the fifth Boston reliever, reached 30 saves for the sixth straight season despite allowing Logan Forsythe's solo homer in the ninth.Brad Miller hit a two-run double in a three-run second that put Tampa Bay up 3-1 and gave him 80 RBI.Tampa Bay threatened in the second but failed to score due to two nice defensive plays. Pedroia made a throw from just in front of the outfield grass at second base on Mikie Mahtook's grounder to get Corey Dickersonat the plate. Third baseman Brock Holt made a solid play along the line onAlexei Ramirez's grounder and threw him out at first to end the inning."We made a couple of really nifty plays," Farrell said. "Petey with a heads-up play and then Brock made a beautiful backhand play to finish the inning."