Spiller sat out last Sunday's loss to the New Orleans Saints with a "nagging" high-ankle sprain. He was limited in practice Wednesday and Thursday this week.
"I feel good about C.J. playing," Marrone said. "In talking with him, without any setbacks, we feel like he'll be ready to go."
Meanwhile, quarterback Thad Lewis remained out of practice Thursday with a rib contusion. Lewis is also dealing with a flu virus.
Multiple reports Wednesday stated that Lewis was expected to start Sunday, but Marrone questioned those reports Thursday.
"I know there was a report out there from a league source," Marrone said. "I'm hoping the league source is right, because I really don't know right now. It's 50-50. Trust me."
Marrone said no decision has been made on Lewis' status for Sunday's game.
In addition, rookie EJ Manuel practiced on a limited basis Thursday as he continues to rehab from a knee injury. Marrone said Manuel will not play Sunday.