Aasgaard was ruled out of the midweek Carabao Cup loss to Sunderland due to a knee injury which is set to keep him on the sidelines for four weeks.
Richardson sought plenty of positives in the defeat to the Black Cats with deadline-day signings Jason Kerr and Curtis Tilt making their respective debuts.
Both will be pushing to start but Richardson will want to keep his line-up close to the one that eased to a 4-1 win at Accrington last weekend.
Cheltenham could be without on-loan Leicester midfielder Callum Wright for up to six months after confirming the extent of his knee injury.
Will Boyle is also out for at least another month but there is better news for boss Michael Duff with Charlie Raglan and Liam Sercombe both pushing to return.
Duff continues to take a cautious approach over Kyle Vassell's comeback from injury with the striker once again coming off the bench against Preston at Deepdale.
Fellow striker Christian Norton will not be rushed into the line-up following his deadline-day loan arrival from Stoke.