Scunthorpe central defender David Mirfin faces up to two months on the sidelines with a knee injury.
The 27-year-old suffered the problem in last weekend's FA Cup defeat at Gillingham and has missed the Iron's last two games, which has seen Brian Laws' men collect six points.
Scans have shown ligament damage, and Mirfin will not return until the new year.
"We have had the scan results and it is not looking good," Laws said after Saturday's 2-1 win at Coventry. "It looks like it could be a minimum of six weeks, but maybe nearer eight.
"He has tweaked his ligament and unfortunately that's the time this injury takes.
"But Niall Canavan has come in and grabbed his opportunity, so for us that was a bonus."