McCluster has a cut on his ankle that has become infected.
He suffered the injury Sunday at Washington.
McCluster has missed the last two days of practice while the Chiefs training staff has worked on cleaning out his wound.
The Chiefs don't know if he has MRSA because test results are not back yet on that.
K.C. can officially punch its ticket to the playoffs with a victory against the Raiders.
Coach Andy Reid says his team knows what's out there.
"There's no time for a mental lapse. You have to be so focused," said Chiefs coach Andy Reid. "Anything's possible, you feel that way anyway. Anything's possible."
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