Scunthorpe will be without suspended winger Mark Duffy for their opening home league fixture.
Duffy received two yellow cards in the Iron's opening-day defeat at Crawley and sits out a one-game ban.
Striker Connor Jennings, who broke a bone in his foot 12 days after joining Scunthorpe from Stalybridge in January, is hoping to make his first league start for the club.
Scunthorpe will still be without central defender and skipper Paul Reid due to a hand injury, so Tom Newey looks set to continue alongside fellow summer signing David Mirfin.
Reid, who injured his hand during the summer tour of Ireland, has been fitted with a lightweight cast and could return to contention for Saturday's home game against Yeovil.
Midfield pair Damien Mozika (ankle) and Michael Collins (Achilles) remain sidelined, but Knill has no other new injury or suspension problems.
Crewe boss Steve Davis will run the rule over midfielder Ashley Westwood and forward Max Clayton.
Westwood went to hospital as a precaution after taking a blow to the head in Saturday's 2-1 defeat to Notts County at Gresty Road.
The Alex captain returned to training on Monday and will be assessed before kick-off.
Clayton suffered bruised ribs following a collision with Magpies goalkeeper Bart Bialkowski.
Alan Martin will continue in goal as Steve Phillips begins his rehabilitation from knee surgery, while Matt Tootle (thigh) and Michael West (heel) remain sidelined.
The Railwaymen are looking to bounce back at Glanford Park after their weekend loss ended a run of 20 games without defeat.