How to play fetch with two dogs and 1 ball?

well, seems that my new dog just follows my dog to get the ball but he never gets it like. my dog will chase and get the ball but my new dog just runs to my dog and jumps on her. he sometimes try to block her not to get the ball. why doesnt my new dog get the ball he gets some balls depends on what ball we play with he will only get rubber ball. my dog just get the hard one but if we only play with one ball only the same dog keeps getting it. and i'm wondering why my new dog chases my dog jumps on her trys to block her and sometimes growls maybe its play growl bt my dog doesnt seem to want to ply like that with him. they are both terrier mixes my dog is 1yr old female my new dog is a terrier 1yr old male.