Dustin Pedroia hit a tie-breaking two-run single in the eighth inning to lift the Boston Red Sox over the Oakland Athletics, 4-2, in the opener of a three-game set between first-place clubs.
Brock Holt also had a two-run single for the AL East-leading Red Sox, whose 58 wins before the All-Star break are the most in franchise history.
John Lackey (7-6) earned the victory after allowing two runs on three hits over seven innings. He was matched pitch-for-pitch by Jarrod Parker, who retired the final 16 batters he faced before being pulled to start the eighth.
"I was moving the ball in and out and being able to get some early contact. That helped me go later into the game after a long inning like that," Parker said.
Jose Iglesias greeted Sean Doolittle (3-3) with a single, and Shane Victorino was hit by a pitch with two outs. Ryan Cook relieved Doolittle, and after Victorino stole second to get himself into scoring position, Pedroia lined a base hit to left to bring in both runners.
Andrew Bailey shook off a leadoff walk in the eighth, and Koji Uehara needed 14 pitches to strike out the side in the ninth en route to his eighth save.
Jed Lowrie hit a solo homer for the A's, who still pace the AL West despite dropping back-to-back games.
The Red Sox jumped on top 2-0 in the second inning on Holt's two-out, two-run single. Mike Napoli and Daniel Nava scored on the base hit to left, with the latter reaching on a hit-by-pitch.
Parker threw high and inside, and Nava ducked and had the ball ricochet off his bat and into the side of home plate umpire C.B. Bucknor's helmet. Bucknor stayed on his feet when he was initially hit but was clearly dazed and was eventually replaced behind the plate by second base umpire Bill Miller. Nava, meanwhile, went to first even though replay showed the ball may have hit his bat instead of his shoulder.
Lackey did not allow a hit until Seth Smith doubled to lead off the fifth inning. John Jaso drove in Smith with a one-out single before Pedroia saved a run by making a diving stop to start an inning-ending double play with runners on the corners.
"I probably didn't have my best stuff like I had my last few times out and still was able to do pretty good against a pretty good team," said Lackey.
Lowrie tied it when he led off the sixth with his seventh home run of the year.
Parker, who also gave up three hits and two runs, has not lost since May 22, a span of nine starts in which he has not allowed more than five hits ... Boston won 57 games before the break in 1978 and 2008 ... The Red Sox had lost six straight at Oakland Coliseum ... Lackey has given up three earned runs or less in 14 of his 16 starts this season ... Red Sox outfielder Jacoby Ellsbury had his 19-game hitting streak snapped ... Boston acquired left-handed reliever Matt Thornton and cash from the Chicago White Sox in exchange for minor league outfielder Brandon Jacobs on Friday.