The Buffalo Bills running back has been struggling with an ankle injury in recent weeks, and has missed the last two days of practice with the AFC East side.
The head coach told the team's official website: "He wants to go, but we've got to make good decisions. He doesn't feel as good in my opinion.
"He might say it, but as far as how he's looked. You see it during the game and you see it out here at practice. We've got to make a good decision, a tough decision.
"My thing is if we put him on that field can we hold him accountable for what we're asking him to do, and if the answer is no or we're not sure or he's a little banged up or he missed practice this week. If we're going to say things like that as coaches then we really don't need to put that player out on the field [even though] he's saying he's ready to go."
Spiller has 362 rushing yards and a touchdown so far this season.