Like Slugger Dad, I don't know you -- I'm just replying to a very short post from a stranger on a discussion group, not the 3-dimensonal people that you and your family are in real life.
That said, I agree with Luv Baseball and Slugger Dad. This doesn't sound like a good or a healthy situation. Unfortunately that's all too common in father-son relationships.
You know the old Mark Twain quote?
"When I was a boy of 14, my father was so ignorant I could hardly stand to have the old man around. But when I got to be 21, I was astonished at how much the old man had learned in seven years."
There may be some of that to it, but as described it's more like the old story you see in movies, books, and real life too often - a hardass dad whose son is never good enough for him, often because he's bitter about his own failures, tries to live through his son's successes, but also roots for his failure to validate his own feelings of disappointment in him.
It's getting pretty late, cause your son is an adult now and like Luv Baseball says, he could go away at any moment and never come back. Who could blame him? But as long as he's around I'd think about family therapy with a shrink or a minister or anybody who can get through to dad what he should have learned a few years back -- that it's not his baseball career, or his life. It's your son's career to do what he will with it. Dad should either support him as best he can, and if he can't enjoy it on those terms, just butt the hell out.