About 20 firefighters tackled a fire at the former home of Scarborough Football Club on Seamer Road in the North Yorkshire resort.
Crews were sent to the site on Friday afternoon after several calls were made to North Yorkshire Fire and Rescue.
Four fire engines were despatched to the McCain Stadium. The fire service said it was started deliberately.
Scarborough FC went bust in 2007 and were reborn as Scarborough Athletic who now share Bridlington Town's ground.