Hi all, I have a little black shih-tzu named Tony. He's smart, charming and well-behaved.....except when he finds a ball at the dog park. Once he has that ball, he won't give it up to anybody. He won't come when I call, he won't be bribed with treats, and you just can't catch him. To him, it's a game of keep away. I'm at the point where I can't take him to the park any longer because of this problem. That really sucks, because his favourite thing to do is run and the park is the only place where he has that opportunity. When a ball isn't involved, he has no issues with coming when he is called. He'll play fetch in the house and drop the toy on command. I'm really at the end of my rope here. Any advice would be very greatly appreciated.