Boston battered Buehrle, handing him his first loss of the season in an 8-1 series-opening victory over the Blue Jays in front of 29,411 at Rogers Centre.
"If he makes his pitches, he's going to get you out. You've seen his numbers coming into this game, he's been dealing," said A.J. Pierzynski, who went 3-for-4 with two runs scored against his former batterymate with the White Sox. "Luckily for us he made some mistakes tonight and we were able to capitalize on them."
The Red Sox struck early and often, scoring a season high in runs and notching a season-high 16 hits. Boston sent seven men to the plate as part of a four-run second. Pierzynski lifted a sacrifice fly, Will Middlebrooks hit an RBI single and Dustin Pedroia drove in two with a single to give Boston a 4-0 lead.
The four second-inning runs the Red Sox scored off Buehrle, who entered the contest with a 4-0 record and Major League-leading 0.64 ERA, were more than he had allowed in his previous four starts combined.
"I think the game was kind of decided there in the second inning," said Buehrle, who allowed seven runs (six earned) on a season-high 12 hits. "I wasn't hitting my spots as good as I was in the past. When I did, they got some base hits, but overall, too many strikes in the middle of the zone and they took advantage of it."
Boston didn't stop after the second-inning outburst, either. David Ortiz hit a one-out solo homer, his fifth of the season, the following inning to put the Red Sox ahead, 5-0. It was Ortiz's 33rd career home run at Rogers Centre, the second most all-time behind Alex Rodriguez's 36. The home run was also the 378th Ortiz has hit as a member of the Red Sox, moving him one shy of tying Dwight Evans for fourth on the club's all-time list.
Buehrle navigated his way out of trouble the next two frames until Boston chased him with one out in the sixth. Middlebrooks, who was activated off the disabled list before the game, came through again, driving a 1-2 offering to right-center field to double in Pierzynski, giving Boston a 6-0 lead.
The 35-year-old Buehrle was yanked after walking Jackie Bradley Jr., who later came around to score on a bases-loaded walk by Toronto reliever Neil Wagner, which put the Red Sox in front, 7-0.
"We had a pretty clear understanding of how [Buehrle] was going to try and pitch us," Red Sox manager John Farrell said. "The most important thing is we waited out those borderline pitches that were good pitcher's pitches that were off the plate to get into some good hitters' counts."
Pierzynski, Middlebrooks and Bradley, Boston's seven-eight-nine hitters, combined to go 8-for-12 with five runs scored and four runs driven in.
Every player in the Red Sox lineup recorded a hit and five of them had a multihit game.
Jake Peavy, who got the nod for the Red Sox, bounced back from a season-worst outing to record his fourth quality start. Peavy got plenty of run support, but didn't need much, hurling a season-high seven innings of one-run ball. The right-hander, who surrendered a mammoth solo homer to Juan Francisco in the seventh, walked two and punched out seven to earn his first victory of the season.
"He has been pitching pretty well all year, we just haven't scored any runs for him," Pierzynski said. "It was nice for him to get his first win and get on the board. He was awesome, he made one mistake, it was the home run. It was really far, too."
Peavy found the zone much more consistently than he had in his previous three games, in which he walked four in each contest, and believes he's turning a corner in that regard.
"My command is coming, slowly but surely," Peavy said. "It has taken me a minute to hone everything in."
The effort the Red Sox put together was a far cry from Thursday's 14-5 loss to the Yankees in which the club recorded a season-high five errors. After playing one of its worst games of the season, Boston turned around and played one of its best.
"Good team win, we needed it after [Thursday night]," Peavy said.