There's one rule to talking sports with T.I. ... put your money where your mouth is ... and the rap star just proved that by straight PUNKING a TMZ photog who tried to make an NFL bet on the street.
T.I. was out in L.A. when one of our photogs dared to ask him about the state of Falcons football, and more specifically how Julio Jones would do against the Eagles this week.
That's when a rich guy (T.I.) told a not so rich guy (our camera guy) to put up (money) or shut up (your mouth).
Best part? Tip's reaction when our guy tells him how much he wants to bet ... priceless.