My dog is what I call Ball Obsessed!! Seriously she could play fetch from dusk till dawn. She is crazy. What I did is give her a treat that I know she loves, couple more pieces so she knew what I had in my hand. Then, I gave her the ball right in front of me and showed her the treat. As soon as she dropped the ball to get the treat I said DROP IT, and gave her the treat. Repeated several times. I used Cherrios because she loves them and gave her about a 1/4 piece each time. Then I threw the ball and she went to get it and I called her and showed her the " cookie" she ran, I said drop it and gave her the cookie. Next time further, sometimes I gave her a treat some times I didnt. Anyways she returns with the ball because she thinks Im going to give her a treat. I dont have to anymore , just until she got the hang of it!