BOSTON (AP) -- The Red Sox scored six runs in the first inning against a wild Ricky Romero, David Ortiz hit his 399th career homer and Boston beat the Toronto Blue Jays 10-4 on Wednesday for its fifth straight series win.
Adrian Gonzalez had three RBIs and Mike Aviles added two as the Red Sox improved to 9-2 in their last 11 games.
Jon Lester (5-5) fell behind 1-0 in the first when he allowed a run-scoring single to Colby Rasmus, but the Red Sox scored all the runs they needed in the bottom half as Romero (8-2) threw 16 balls on his first 19 pitches.
Boston went ahead 7-1 in the second when Ortiz and Cody Ross walked on 3-1 pitches and Gonzalez hit an RBI single.
Jose Bautista hit a solo shot, his major-league leading 25th homer of the season, off Lester in the fourth. But the Red Sox struck back with two runs in the bottom of the inning. Gonzalez singled in one and Aviles drove in the other.
Ortiz made it 10-2 in the fifth with his 21st homer of the year. His 399 career homers are tied for 49th with Andres Galarraga and Al Kaline. Duke Snider is 48th with 407.
Lester, who was just 1-2 in his previous six starts, retired eight consecutive batters before running into trouble with two outs in the sixth. He allowed a double to Bautista followed by Edwin Encarnacion's 22nd homer. Ben Francisco then singled, but Yunel Escobar flied out to end the inning.
Lester pitched seven innings, striking out four with no walks, seven hits and four runs.
Romero was in trouble from the start. He had averaged 4.4 walks per nine innings this season but walked a total of just nine batters in his last four starts.
On Wednesday, he struggled to find the plate and left after giving up six walks, seven hits and nine runs in three-plus innings.
He walked leadoff batter Daniel Nava on four pitches then threw two balls to Dustin Pedroia before his first strike. Pedroia doubled in Nava and the next batter, Ortiz, walked on four pitches before Romero started Cody Ross with two more balls.
Ross then singled, loading the bases, and Gonzalez reached on an error by third baseman Encarnacion, allowing Pedroia and Ortiz to score. Will Middlebrooks followed with an RBI groundout, Aviles singled in one run and Darnell McDonald singled in another, making it 6-1.
Notes: Toronto, in last place in the AL East, dropped two games behind Boston ... Romero was 4-0 in his last seven starts but had given up at least four runs in each of his last six games. Wednesday's start was his shortest of the season and the runs allowed were his most.... Bautista leads the majors with 16 road homers. ... RHP Henderson Alvarez, who left Monday night's 9-6 Toronto win with right elbow soreness, is expected to start on Saturday after undergoing an MRI that shows some inflammation, manager John Farrell said.