North Melbourne will be missing two of its most experienced defenders on Sunday with Daniel Pratt joining Michael Firrito on the sidelines for the match against Adelaide.

Firrito was ruled out after accepting a one match ban from the match review panel and now Pratt will miss through an injury he sustained while playing against Sydney.

The courageous backman fractured the thumb on his right hand before the halftime siren sounded at Etihad Stadium on Saturday. After receiving treatment in the rooms, he was able to play on despite the break.

After a series of scans he was sent to hospital on Monday to have a plate and screw inserted. He returned to Aegis Park on Tuesday with his hand in plaster and his arm in a sling.

Pratt is expected to miss up to a month of football.