By C. Trent Rosecrans
Jon Lester left Tuesday's start against the Blue Jays after four innings with a strained latissimus muscle and will miss his final start of the first half, the Boston Globe reports.
Reliever Alfredo Aceves has been told he will start in Lester's place on Sunday, according to the newspaper.
Lester hadn't allowed a hit before exiting the game and Matt Albers retired five batters before allowing his first and only hit in two innings, earning the victory. The Red Sox used three more relievers the day after using four relievers to make up for John Lackey's 2 1/3-inning start.
The Red Sox will have their left-hander examined on Wednesday.
"We'll certainly get him checked out extensively tomorrow," Francona told reporters. "That good sign of it, I think, is that he didn't do it on one pitch. Between innings, it felt like it was cramping on him. There's no way we're going to let him pitch."
If Lester goes on the disabled list, he could return July 22, the sixth game after the All-Star break.
"It should be fine," Lester told reporters. "Hopefully for the rest of the season. I don't think it's a long-term issue."
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