Two fire crews from Rotherham station were called to a fire at a disused leisure centre at 7:15pm on Wednesday.
Firefighters on arrival at the boarded up centre on Charnwood Road in Swinton found a fire near the squash courts which had also spread to the cavity wall.
Crews wearing breathing apparatus used a hose reel to put the fire out, which is believed to have been started deliberately.
Firefighters left the scene at 8:40pm.