Hamilton, who had started all 22 games, left Sunday's game against Tampa Bay after two innings after feeling a spasm in his back when he hit a first-inning single.
He indicated after Sunday's game that he would be able to play on Monday, but before the game manager Ron Washington said Hamilton still felt some discomfort.
"He came in with some discomfort, so we're still in a day-to-day mode," Washington said. "We'll just wait and see how everything goes today and then tomorrow make a decision on him. But right now he's day to day."
Washington said the problem is muscular and added that the artificial turf at Rogers Centre was not a factor in the decision.
"We're not going to let the turf stop us from putting our best team out there unless it's detrimental," Washington said. "He's just got some stiffness and we have to wait until he can do what he has to do comfortably. "
Washington did not discount the possibility of Hamilton perhaps being used as a pinch-hitter on Monday. He entered Monday batting .395 with nine home runs and 25 RBIs.