David Worrall is the latest injury worry and the midfielder is rated as a major doubt after limping off the training ground on Thursday morning with a knee injury.
"It doesn't look good," Knill told his club's official website.
"He wasn't even near anyone; he just went over and feels his knee.
"I'd have to say that he is doubtful for now, but we will monitor it."
Ryan Lowe (hamstring) and Mike Jones (foot) are also doubts as the pair have not trained all week.
Andy Bishop and Damien Allen (both groin) are both still sidelined following their respective surgeries as is Andy Morrell (ankle), who should return to training next week. Danny Carlton (Achilles) is also absent for the Shakers.