I went to school for audio/video/tv production and took a few classes in actually being talent and it's not something everyone can do. Pretty much everything is scripted at least somewhat including live sporting events. If you have noticed for the most part most broadcasting teams have a mix of professional broadcasters and former players. Even though it's not baseball I think the best example of this I can remember would be Inside the NBA in the 2000s where Ernie Johnson played point guard in the broadcast with Kenny and Charles. He was the one that kept the show moving forward and everyone on target.