Erik Bedard picked up his first win since being acquired by the Red Sox. Bedard (5-9), who was obtained at the non-waiver trading deadline on July 31, allowed five hits and three runs over six innings. He also had six strikeouts to post his first victory since June 15 against the Angels.
"I threw a lot of pitches in the first couple of innings, tried to battle," Bedard said. "I threw strikes and kept the ball down, got through six (innings)."
Josh Reddick had four hits and scored three times for the Red Sox, who remained a half-game behind the first-place Yankees in the AL East. New York rallied to beat Toronto, 6-4, earlier Saturday.
Jarrod Saltalamacchia's two-run homer started the scoring in the fourth inning.
Colby Lewis (11-10), who was charged with seven hits and four runs over 3 1/3 innings, has just one victory in his last eight appearances. Yoshinori Tateyama also struggled in the fourth inning, giving up two hits and four runs. Merkin Valdez was touched for three hits and a run in the fateful fourth, when the Red Sox sent 13 men to the plate.
"Command, couldn't get the ball down," Rangers manager Ron Washington commented about Lewis' struggles. "You keep giving these guys opportunities with runners in scoring position, they're going to come through. They finally did."
Esteban German smacked a pinch-hit homer for the AL West-leading Rangers, who won, 10-0, in the opener of this weekend series.
Boston left the bases loaded in the first inning and Texas went ahead on David Murphy's RBI single in the second.
Michael Young's RBI base hit highlighted a two-run top of the third, but Jed Lowrie's liner into center field got Boston on the board in the bottom half.
Saltalamacchia tied the game with a homer to right field in the fourth. The Red Sox eventually loaded the bases with two outs, and pinch-hitter Mike Aviles gave the hosts the lead with a line drive single into right field. Crawford was up next and homered to right field.
Jacoby Ellsbury added an RBI single later in the fourth to give Boston a huge 9-3 lead.
Pedroia nearly hit a grand slam, but had to settle for a three-run double that went high off the wall in center in the sixth for a 12-3 advantage.
Boston has outscored the Rangers 42-14 in their four wins vs. the club this year but has been outscored 40-11 in five losses to Texas in 2011...The Red Sox are 30-11 during the daytime, the second-best day record in the majors this year behind the Yankees (36-9)...This marked the third straight game that the Red Sox sent a left-handed starter to the mound. According to Elias, the last time the Sox started lefties in three straight contests was in 1995 with Vaughn Eshelman, Zane Smith and Rheal Cormier, respectively.