Charles came up gingerly after a play and walked to the sideline under his own power. He was walked to the medical tent and shortly after taken to the Griffon Indoor Sports Complex in the front of a cart.
Head coach Andy Reid called the injury a strain after practice and that x-rays had come back negative. Reid also said Charles will be evaluated day-by-day, but still intends to play him if he's healthy Friday night when the Chiefs host the 49ers.
"If he can go, he'll go," Reid said. "We'll see. We'll see how he does in the next little bit. We'll see where he's at with pain or swelling."
Rookie Knile Davis got reps with the first team after the running back left practice.
Charles missed most of the 2011 season after tearing his ACL in Week 2.