At 20 years old there will be a time this season where they will want to limit his innings. Bringing him up to work in relief might be a good way to do it. If they think he can be a valuable piece to the bullpen, they may feel like they get a great arm without trading any assets to do it for August and September. In an ideal world, they can start using him in low leverage situations and if he can get outs, gradually increase his use in bigger situations. Having him come now for a look will keep him motivated as the dog days of summer roll in.