That's Josh Jacobs -- former Alabama superstar and current Oakland Raiders starting RB -- dropping the biggest bombshell about Nick Saban ever ... and we can't stop laughing!!!

Jacobs appeared on "The Dan Patrick Show" on Friday ... and when DP asked Josh for his favorite story of Bama's head man -- Jacobs didn't hold back, saying the guy LOVES the toilet bowl humor!!!

"It's funny because I hadn't heard one of them since middle school," Jacobs says of the "deez nuts" jokes. "And then Saban, when I went to college, Saban used to do it a lot."

Jacobs then proceeded to tell the funniest Saban story you'll ever hear ...

"Alright, so one day, I caught like five passes in a row, and he was like, 'Hey, hey, Josh. If you want to hold all the balls, hold deez.'"

"I was like, 'What, coach?' So I just sat there for second and I was like, did he really just say that to me?!"

That's right, 67-year-old Saban -- winner of 6 national championships -- is clowning all his players on a regular basis with one of the most childish jokes ever.