How can I increase player morale?

Is the only way to increase morale for players to constantly feed them the ball (at least for offense) and to do well, hoping you get the chance to praise them?

My star RB has been stuck at incredibly low morale ever since I was hired to the team. This means he performs incredibly poorly and it’s nearly impossible to both do well and utilize him very much.

Essentially I’m ending up in a vicious cycle of running the ball poorly game after game due to his poor morale, but I can’t get his morale up because the run game is terrible and I can’t seem to make anything happen (doesn’t help that he’s a low-ranked player, but still better than a non-star RB).

Am I just kinda SOL until the draft? I don’t have the credits to sign a free agent because, naturally I’m playing so poorly.

This question applies to other positions as well, especially defense, where you have absolutely no control over any of the players whatsoever.