Can I collide with a defender in hopes of knocking the ball away on an unforced out in baseball?

Can I collide with a defender in hopes of knocking the ball away on an unforced out in baseball?

Alan Jaeger (Pitching Coach / Founder) gives expert video advice on: What is a 'base runner' in baseball?; What do I do after I hit a fair ball?; After I hit a fair ball how should I judge how many bases I can take? and more...

You're allowed to collide with a defender in the hope of knocking the ball out and being safe if the defender is guarding the base that you're going to, or if the defender has the ball in his hand and you both meet at one point. However, you cannot make contact with a defender if he's not guarding the base and he does not have the ball in his possession yet.