Cody Ross hit a three-run homer with one out in the bottom of the ninth to give the Boston Red Sox a 3-1 win over the Chicago White Sox on Thursday night.
It came one night after Ross hit three-run homers in consecutive innings of a 10-1 win.
Boston took three of four games in the series and is 5-2 since the All Star break.
It was the fifth loss in 13 games for AL Central-leading Chicago, which opens three-game series at second-place Detroit on Friday night.
Matt Thornton (2-6) got one out, but left with runners on first and second before Addison Reed faced Ross, who hit a 1-1 pitch into the Green Monster seats.
Carl Crawford opened the ninth with a single, but was erased on Dustin Pedroia's fielder's choice grounder. Adrian Gonzalez then singled to right before Reed came in. Just before the first pitch, Boston sent Nick Punto in to pinch run, slowing Reed down a bit.
Alfredo Aceves (1-6) pitched one inning for the win.
Boston's Clay Buchholz had a solid start, allowing one run, six hits, striking out six and walking one in eight innings.
Chicago rookie left-hander Jose Quintana continued the impressive start to his career, pitching eight shutout innings, before Boston's comeback win.
Quintana held Boston to five hits, striking out two and not walking a batter in his 10th major-league start. The 23-year old has held opponents two runs or fewer in eight starts.
Buchholz had been given the second-most run support in the majors at 7.48 runs per nine innings — only behind teammate Felix Doubront's 8.38 per — but the Red Sox couldn't solve the rookie lefty.
Boston was held to one hit until loading the bases with one out in the seventh on singles by Pedroia, Gonzalez and Ross. Shortstop Alexei Ramirez was leaning the wrong way on Will Middlebrooks' liner, dove back, grabbed the ball on one hop and fired to second to start an inning-ending double play.
The White Sox grabbed a 1-0 lead in the fourth when Adam Dunn drew a leadoff walk and advanced to third on Paul Konerko's single, barely beating right fielder Ross' throw. Alex Rios followed with his sacrifice fly to center and Dunn trotted home easily.
Unlike Wednesday night when the Red Sox pounded a rookie left-handed starter for eight runs, three homers and 12 hits in four innings, Boston had just Pedro Ciriaco's two-out triple in the third.
Second baseman Pedroia returned from the 15-day disabled list after being out with a strained right thumb and went 1 for 4.