Well, this is fun. Not as fun as NBA summer league, but still.

Draymond Green got into it with Conor McGregor over an Instagram post in which McGregor, the UFC star who is prepping for his Aug. 26 bout against Floyd Mayweather, is wearing a vintage Golden State Warriors jersey. Green, the Warriors’ trash-talking star, was none too pleased.

“We rocking with Floyd, bro, not you. … take that off bruh,” Green wrote.

The shirt may bear Green’s No. 23, but it’s actually a C.J. Watson jersey and McGregor wasted no time in replying: “That’s C.J. Watson mate. I don’t know who the [expletive] you are. No disrespect tho kid, keep hustling and stay in school.”

McGregor wasn’t finished there, delivering another shot. “Now ask yourself why I’m rocking C.J. when I don’t know or given a[n] [expletive] about basketball,” the Irishman wrote. “I dribble heads off the floor. Not a basketball. This is no game here, kid.”

There’s some speculation that McGregor was sending a subtle message with his jersey choice. In 2010, Watson reportedly played a minor role in Floyd Mayweather’s domestic abuse conviction, SFGate.com’s Katie Dowd writes. Josie Harris, who was Mayweather’s girlfriend at the time, told police that Mayweather had assaulted over her “affectionate text messages” with Watson. Mayweather was sentenced to 90 days in jail, 100 hours of community service and a 12-month domestic-violence program. He also was fined $2,500.