Think of it this way. If you are driving to a location where you regularly work (office or playing field), then these are commuting miles and are not deductible. If you drive to a temporary (or non-regular) work location, then these are business miles (whether or not you drive there from your home, office or regular playing field).
So if you drive to your office then 10 miles to a temporary playing field location then back to office, you have 20 business miles (10 each way from office to temporary location and back to office). If you drive from your home 8 miles to a temporary playing field location then back to home, you have 16 business miles for the round -trip. If you drive from home to office then to a temporary work location (10 miles) then home (8 miles), you will be able to deduct 18 miles (the travel to office from your home is considered commuting miles).
