The 18-year-old central defender caught the eye in the Iron's Carling Cup victory against Swansea a fortnight ago, but sat out the defeat to QPR with an ankle injury.
But Canavan is available for Saturday's clash at Crystal Palace and Crosby has challenged him to keep some of his more experienced team-mates out of the side.
"If you asked Niall if he thought he would be in and around the first team, he would probably say no," Crosby told the Scunthorpe Telegraph.
"But once you get an opportunity you have got to take it. No matter how you get it, some people's misfortunes are other people's gains."