BOSTON -- Mark Buehrle got his major league-leading eighth victory with a big boost from Toronto's powerful lineup.
Neither was surprising.
Buehrle (8-1) has eight wins through May for the first time since 2002 and an ERA of 2.16. He gave up two runs in the first two innings, but by then Toronto had seven, starting with homers on consecutive pitches by Melky Cabrera and Jose Bautista in the first inning.
That gave the Blue Jays a major league-high 67 home runs and gave Buehrle a big cushion.
The 15-year veteran lefty blanked the Red Sox for his final five innings and allowed seven hits and no walks while striking out five in seven innings.
Dustin McGowan pitched two shutout innings as the Blue Jays took a half-game lead over the New York Yankees in the AL East.
"It's nice, obviously" to lead the majors in wins, "but I've always said you can go out your next eight starts and [stink] and be under .500," Buehrle said. "I try to throw it out the window and get ready for my next start."
Toronto improved to 8-2 in its past 10 games, while Boston lost its seventh straight. The Red Sox went 0-6 on their homestand, the first time since June 1994, when they also lost six in a row at Fenway Park, that they were winless on a homestand of at least six games.
"We're in a stretch of games here where we're giving up too many runs early and we're scuffling to score runs," Boston manager John Farrell said. "That's a dangerous combination."
Red Sox ace Jon Lester (4-6) had his worst outing of the season, allowing seven runs and seven hits through 1 1/3 innings. Then he settled down and retired 12 straight batters before giving up a single to Kevin Pillar with one out in the seventh. But Pillar was caught stealing.
Lester left with one out in the seventh after allowing 10 hits and striking out just three. He had averaged an AL-best 10.83 strikeouts per nine innings.
"The list goes on and on of things that I just flat out didn't do," Lester said. "I just wasn't able to do it with anything. Pick a pitch, I wasn't able to do it."
Buehrle retired 11 of his last 12 batters. He began the day tied with Zack Greinke, Rick Porcello and Adam Wainwright with seven victories each. The Dodgers' Greinke was scheduled to pitch against the New York Mets on Thursday night.
Buehrle's only loss came at home against Boston on April 25 when he allowed seven runs in an 8-1 loss.
Lester retired the first batter of the game, Jose Reyes, on a grounder. But Cabrera hit a 1-0 pitch for his eighth home run and Bautista followed with his 12th.
"You never anticipate that because [Lester's] one of the best," Gibbons said.
In the second, six of Toronto's first seven batters reached base on five hits and a walk. Steve Tolleson and Pillar singled and moved up on a sacrifice bunt by Anthony Gose. Reyes doubled in both runners and stole second. Cabrera walked and Bautista and Edwin Encarnacion followed with RBI singles. Bautista came across when Brett Lawrie grounded into a forceout at second, making it 7-1.
Toronto manager John Gibbons lost a challenge in the sixth when the on-field ruling that Pillar was caught stealing was upheld. ... Bautista has reached base in 48 of his 49 games. ... Boston has been outscored 37-16 in its seven-game losing streak, its longest since dropping its last eight games in 2012. ... The Red Sox open a three-game series against Tampa Bay on Friday night with John Lackey (5-3) facing Chris Archer (3-2) of the Rays. Toronto returns home to start a three-game set with Oakland, with Liam Hendricks (0-0) pitching against Scott Kazmir (5-1) of the Athletics. The Blue Jays called up Hendricks on Thursday from Triple-A Buffalo, where he was 5-0. R.A. Dickey's start was moved from Friday to Saturday.