Reggie Bush -- Busts Up Over Barry Sanders Convo

Reggie Bush fielded the greatest question of his football career last night -- and by the greatest, we mean the funniest ... because even Reggie couldn't hold back his laughter.

Reggie was in Bev Hills when we brought up his new 4-year, $16 million contract with the Detroit Lions -- and you can't talk Lions running backs without talking about the legendary #20, right?

So ... the question: "Do you think you could possibly be the next Barry Sanders?"

Once you stop laughing ... watch the clip to see Reggie's reaction.