Hitting .283 with a .319 OBP in high-A isn't going to cut it. He needs to hit closer to .300 or draw more walks to make it work.
.283 for a 21 year old guy from the Dominican where all the prospects are unbelievably unpolished is pretty respectable. the OBP is something he needs to work on but there are guys in the majors who are just as bad at getting on base. see desmond, ian