I use a kong to play fetch. I've had dogs that just weren't interested in this game at all and others who were naturals. You might want to start indoors with a long line attached so when your dog picks up the ball you can say "Bring it here" or whatever and then gently reel you dog to you with much encouragement and praise as he finally "comes" to you. A tiny food reward could help cement the understanding of what is wanted. Once your dog understands what is expected, the challenge is to make it fun for him. My Hannah loves to play fetch. Tucker isn't too interested. Sometimes he will run after the kong and pick it up but then just drop it and walk away. He used to be better when I would reward with a treat, but a game of fetch should be a reward in and of itself, so I stopped that and he stopped retrieving.