Just days after Will Smith was shot and killed in an apparent road rage incident ... another NFL star says he was a passenger in a similar situation where things got thiiiis close to getting violent.
Denver Broncos linebacker Brandon Marshall just tweeted about the situation ... saying, "My uber driver a G, Somebody cut him off and almost hit him. And he pulled up to the side of him and got out the car and told him to get out."
What's especially scary is the fact Marshall says his driver got OUT of the car to confront the other guy .