BOSTON -- Jon Lester pitched into the eighth inning before leaving with an apparent injury, and Dustin Pedroia homered in a seven-run second to help the Boston Red Sox beat the Toronto Blue Jays 7-4 in the opener of a four-game series Thursday night.

Toronto, which reeled off 11 straight wins this month, had won 12 of its past 14 games and 15 of 19 to close within 6 1/2 games of the AL East-leading Red Sox.

Then the Blue Jays ran into Lester.

The left-hander retired 10 straight to begin the game and didn't allow a hit until the fifth. He came out after giving up consecutive singles to start the eighth and running the count to 3-0 on Emilio Bonifacio.