"He got hit hard tonight, there's no doubt about it," manager Joe Girardi said of Burnett.
Toronto won its fifth straight, assured itself of at least a .500 finish and temporarily denied the Yankees the chance to clinch a playoff berth. Boston's 6-1 road win over the Chicago White Sox ensured New York would have to wait at least another day.
"Hopefully it means we're getting it out of our system," Teixeira said of New York's September swoon. "We haven't played good baseball. That's starters, that's offense, defense, it's everything. Let's get this out of our system and hopefully we do make the playoffs and have a chance to win a World Series."
Asked whether Burnett (10-15) could be counted on to pitch in the playoffs, Girardi refused to answer.
"I'm not going to talk a whole lot about playoffs until we know we're in," Girardi said. "You've got to get there first and we're not there."
Burnett said his struggles haven't dented his appetite for postseason baseball.
"I expect to start in the postseason," he said. "I just want the ball."
The Blue Jays lead the major leagues with 243 home runs this season, one shy of the team record set in 2000.
Toronto left-hander Marc Rzepczynski (3-4) allowed two runs and four hits in five innings to win consecutive starts for the first time this season. He walked three and matched a career-high with nine strikeouts.
"I felt like that was the best I've thrown the ball all year," Rzepczynski said. "I had slider, fastball, was getting ahead and able to expand after that."
"That was a big game for us," Blue Jays manager Cito Gaston said. "No matter what happens the rest of the way out, this team has done a great job this year."
Burnett, who has lost seven of his past 11 starts, allowed seven runs and seven hits in 2 1/3 innings, his second-shortest start of the year. The right-hander, who walked one and struck out one, is 0-3 with a 9.61 ERA in four starts against his former team this season.
"You can't live in the middle of the plate and that's what I did," Burnett said. "I fell behind every hitter.
"Even the outs I got were hard-hit balls," added Burnett, the first Yankees pitcher to lose 15 games in a season since Melido Perez went 13-16 in 1992.
Jose Bautista opened the scoring with an RBI groundout in the first and Buck doubled the advantage with a leadoff homer to left in the second, his career-high 19th, before the Blue Jays chased Burnett with a five-run third.
Lyle Overbay doubled and scored on Buck's single to center and Burnett was yanked after Adam Lind singled through the right side. Jonathan Albaladejo came on and gave up a sacrifice fly to Edwin Encarnacion, then got John McDonald to fly out.
Granderson homered into the second deck in right off Rzepczynski in the fifth, his 24th of the season, and Teixeira chased Tallet with a one-out blast to center in the seventh for his 33rd of the year.
Rzepczynski recorded eight consecutive outs by strikeouts between the first and fourth innings, a streak that started when Alex Rodriguez fanned to end the first. Robinson Cano struck out to start the second and, after singles by Marcus Thames and Austin Kearns, Rzepczynski struck out Granderson and Francisco Cervelli.
"We've faced him a few times this year and I've never seen him that good," Teixeira said. "His ball was moving everywhere. It's like swinging at a ghost out there. You didn't know what it was going to do."
The streak ended when Cano flied out to right. Thames then struck out to end the inning.
By striking out six straight batters, Rzepczynski matched Ted Lilly's team record set Aug. 23, 2004, against Boston.
Yankees catcher Jorge Posada said closer Mariano Rivera needs to vary his rhythm and be quicker to the plate to avoid a repeat of Sunday's game against Boston, in which Rivera allowed four stolen bases in the ninth inning. Rivera, who has blown saves in three of his past six appearances, worked on his mechanics before the game with pitching coach Dave Eiland. ... Blue Jays 2B Aaron Hill, stuck in a 2-for-22 slump, was held out of the starting lineup and replaced by McDonald.