Just before 1:00 North West Fire Control received reports of flames visible over a wall of the Moss Rose stadium, home to Macclesfield Football Club.
When they arrived, they found an outbuilding adjacent to the club's shop well alight.
Two firefighters wearing breathing apparatus extinguished the blaze using hose reel water jets. They remained at the scene until 4:30, damping down and using a thermal imaging camera to check for hotspots.
An initial investigation indicates that the fire was started deliberately. Cheshire Police attended the incident.
Anyone with information can call Cheshire Police on 101.
