Mix sugar, flour, and fruit. Place pre made pie crust in pan and spread fruit out along with it.
To make crumble mix the oats flour brown sugar and both forms of butter. Use clean hands to mix until small balls have joined together but is still crumbly.
Sprinkle crumble over the filled pie crust and bake for 40 minutes at 350 degrees Fahrenheit. Cool for 5 minutes before serving.