Tampa Bay defeated Seattle to move into the American League East lead when the slumping New York Yankees lost to Boston.
In the National League East, Philadelphia trimmed its magic number to two by beating the New York Mets and Atlanta lost to Washington.
Red Sox 10, Yankees 8 — Andy Pettitte was chased early, ineffective in his second start since being activated from the disabled list, and the Boston held off New York.
Jed Lowrie hit a three-run homer off Pettitte and went 4 for 4, setting a career high for hits. Bill Hall added a three-run shot against Jonathan Albaladejo, handing Red Sox starter Josh Beckett a 10-1 cushion in the fifth.
Alex Rodriguez rallied the Yankees with a pair of home runs, giving him 610 to pass Sammy Sosa for sixth place on the career list. Mark Teixeira also connected twice as New York went deep a season-high six times, yet fell a half-game behind Tampa Bay with its third straight defeat. The Rays beat Seattle 5-3.
Rays 5, Mariners 3 — Willy Aybar drove in two runs, and Rafael Soriano set a team record with his 44th save of the season for Tampa Bay.
Tampa Bay reduced its magic number to three to clinch the franchise's second playoff berth.
Aybar hit a tiebreaking RBI single and later scored on a passed ball during a three-run fifth as the Rays went ahead 5-2. Ben Zobrist drove in the other run with a bunt single.
Soriano, the fourth Tampa Bay reliever, pitched the ninth to break Roberto Hernandez's franchise save record set in 1999.
Rays third baseman Evan Longoria is scheduled to miss the three-game series because of a left quadriceps strain and will be evaluated on Monday.
Seattle's Jason Vargas (9-12) lost his seventh straight start, which is one off the team record held by Randy Johnson (1992) and Rick Honeycutt (1980).
Phillies 3, Mets 2 — Joe Blanton threw seven strong innings, Carlos Ruiz hit a tie-breaking RBI single and Philadelphia won its 11th straight.
The winning streak is Philadelphia's longest since a 13-game stretch in 1991.
Blanton (8-6) allowed two runs and six hits, striking out six. Ryan Madson worked a perfect eighth, and Lidge finished for his 27th save in 32 chances and fourth in four games.
Closer Brad Lidge allowed a one-out double to Ike Davis. He retired Angel Pagan on a fly out to deep left-center and walked Josh Thole before pinch-hitter Jesus Feliciano struck out to leave the tying run at third. Feliciano bounced out to Lidge two pitches earlier, but the play was waved off because Mets manager Jerry Manuel called a timeout to insert Luis Castillo as a pinch-runner for Thole.
Nationals 8, Braves 3 — Adam Dunn hit two home runs and drove in five runs, Willie Harris hit an inside-the-park homer and Jordan Zimmermann won his first game in 15 months as Washington sent the reeling Braves to their fourth straight defeat.
The Braves, who were swept in a crucial three-game series by first-place Philadelphia, began the day one-half game ahead of San Diego in the NL wild card race. Washington, which won its fourth straight — its longest winning streak of the season — denied retiring manager Bobby Cox his 2,500th win in his 4,500th game as a major league manager.
Dunn, who missed Thursday's game with elbow and hamstring injuries, hit both home runs off Nationals nemesis Tim Hudson.