Remember, it was just 7 months ago ... Gelo -- along with 2 teammates from UCLA -- were detained in China after stealing several pairs of designer sunglasses and other accessories from multiple stores in Hangzhou.

UCLA -- along with Chinese billionaire Jack Ma -- worked with Chinese officials to bring the players back home. LiAngelo left UCLA a short time later and moved to Lithuania to play pro ball overseas.

Now, Ball is joking about the whole situation for Foot Locker's new "One and Done" campaign ... in which the host brags that the new apparel is an "absolute steal," while cutting to Gelo.

The host jokingly realizes his mistake and says he meant to say, "The price is so good it must be criminal."

Get it?! Good times ...