The Natural is so over the top it's laughable. He doesn't just knock the cover off the ball, he literally knocks the cover the over the ball. He doesn't just hit a homerun, he hits it into the lights and practically starts a meteor shower. Nothing can ever just happen in that movie. Everything has to be cranked up to a ridiculous degree but I suppose it's entertaining even if you have to constantly roll your eyes at it.
Pride of the Yankees, on the other hand, is just plain bad. It is incredibly wooden and amateurish. Like I said earlier, it's a one scene movie. It's remembered for that Gehrig speech but it's shockingly inept up to that point.