Removing leaves as they fall is recommended to reduce reinfection. Anti-fungal sprays are effective as a protective layer on new leaves in spring, not to treat already infected leaves. I suggest you identify the fungal issue now and make treatment plans for next year. There are some rust diseases which require treatments applied by professionals rather than homeowners.
To identify the disease on your tree, consider taking leaf samples to the Master Gardener Volunteers at the Washington County office. Call to confirm the available times: Office: <personal data hidden>. The directions are at the bottom of this webpage.
Alternatively, post photos here. Top and lower leaf surface and an overall tree photo.