BOSTON — Cody Ross' three-run home run with one out in the ninth inning gave the Red Sox a 3-1 victory over the White Sox Thursday night at Fenway Park.

It was Ross' third three-run home run in the last two days. He now has 16 home runs and 50 RBIs this season.

Boston trailed 1-0 entering the ninth.

With one out in the ninth and with Dustin Pedroia on second and Adrian Gonzalez on first, Chicago closer Addison Reed entered to replace Matt Thornton, who began the inning. But on Reed's second pitch, a 1-and-1, 95-mph fastball, Ross unloaded his game-winning blast into the seats over the left field wall.

Thornton took the loss, falling to 2-6 with a 3.86 ERA. Reed was charged with his third blown save.

The White Sox wasted a sterling effort by Chicago rookie left-hander Jose Quintana, who virtually shut down the Red Sox offense for the first eight innings. Over the first six innings, Quintana allowed just one Boston baserunner, on a Pedro Ciriaco two-out triple in the third.

Quintana went eight scoreless innings, giving up five hits with no walks, two strikeouts, and a wild pitch.

The White Sox scored in the fourth when Adam Dunn led off with a walk off Red Sox right-hander Clay Buchholz. Paul Konerko followed with a single to right, sending Dunn to third. Alex Rios' sacrifice fly to right scored Dunn, giving Chicago the 1-0 advantage.

Buchholz went eight innings, giving up one run on six hits and a walk, with six strikeouts.

Before the ninth, Boston had its best scoring chance in the seventh inning. After Carl Crawford grounded out, consecutive singles by Pedroia, Gonzalez, and Ross loaded the bases for Will Middlebrooks. But Middlebrooks hit into a double play, as shortstop Alexei Ramirez snared, then dropped his line drive. Ramirez threw to second baseman Gordon Beckham for one out, and the relay to first baseman Konerko ended the inning.

By pitching a scoreless ninth inning, despite giving up two hits, Boston right-hander Alfredo Aceves earned the win, his first of the season, improving to 1-6 with a 3.97 ERA.