McElwain, who is starting his third season at CMU, was told by doctors to miss Saturday's game. Newly minted assistant head coach Tim Skipper will lead the Chippewas against the Tigers (4 p.m. ET, SECN).
"Coach Mac has prepared us for situations like this," Skipper said earlier this week. "I've been with him a long time, and he's always talking about 'setbacks are temporary.' So we're moving forward as a team."
McElwain, the former head coach at Florida, is 11-9 in two seasons at Central Michigan, including a 3-3 mark in 2020.
The Associated Press contributed to this report.