Jays starter Matt Boyd failed to record an out, allowing the six batters he faced to at least reach first base and giving up seven runs, including homers for David Ortiz and Hanley Ramirez.
Another followed as the entire Sox line-up apart from last hitter Ryan Hanigan reached base, and Toronto never recovered in a 12-6 defeat.
The win takes Boston, bottom of baseball’s closest division, within six wins of leaders the Baltimore Orioles – who lost 2-0 to the Texas Rangers, both runs coming in the ninth inning.
Baltimore share the division lead with the New York Yankees, who did not play on Thursday, while the Blue Jays and the Tampa Bay Rays – beaten 5-4 by the Cleveland Indians on Mike Aviles’ extra-inning home run – are one game behind.
The Minnesota Twins closed the gap on AL Central leaders the Kansas City Royals to 3.5 games with a 2-0 win as the teams met at KC’s Kauffman Stadium. Kyle Gibson pitched eight scoreless innings.
The Oakland Athletics beat the Seattle Mariners 4-0, helped by Marcus Semien’s homer and Scott Kazmir’s eight-inning shut-out.
The Pittsburgh Pirates beat the Detroit Tigers 8-4 as they bid to make a contest of the National League Central, where leaders the St Louis Cardinals have the Major League’s best record but lost 5-3 to the San Diego Padres on Will Venables’ two-run shot in the 11th.
The Chicago Cubs also kept themselves in contention, beating the New York Mets 6-1 for a season sweep. They and Pittsburgh trail St Louis by 8.5 and six games respectively.
The Mets did not lose ground on NL East leaders the Washington Nationals, who lost 2-1 to the Atlanta Braves. The three teams are covered by five games.
Miami Marlins pitcher Jose Fernandez returned from “Tommy John” elbow surgery to strike out six batters in as many innings and hit a home run in a 5-4 win over the San Francisco Giants.
Adam Lind drove in the winning run in the 11th inning as the Milwaukee Brewers beat the Philadelphia Phillies 8-7, while the Arizona Diamondbacks won 8-1 against the Colorado Rockies.