Though X-rays were negative, manager Joe Girardi said that Giambi was not available as a pinch-hitter during Wednesday's game because he felt as though he could not push off his back foot.
With the Yankees playing a day game on Thursday, Girardi was unsure if Giambi would be ready.
"I don't know. We'll see," Girardi said. "We'll have to see how he wakes up and responds. He had a lot of treatment [on Wednesday]."
Wilson Betemit, starting at first base in place of Giambi, homered off Toronto starter Jesse Litsch in New York's 5-1 victory. Giambi is hitting .253 with a team-leading 11 home runs and 29 RBIs in 48 games for New York.
Bryan Hoch is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.