9:04 AM PT -- TMZ Sports has obtained the police report which says officers responded to the call of a male driver passed out behind the wheel of a black Rolls-Royce SUV.
Cops say when they responded to the scene, they found the SUV -- with the engine running -- in the middle of traffic ... with Broner "unconscious, but breathing" in the driver's seat.
Cops say they tried to bang on the window to wake Broner up -- but ultimately needed to shake the car to get a response from Adrien.
Once he woke up, a confused Broner rolled down his window, and a cop reached inside the car and put it in park.
Officers ultimately got Broner out of the vehicle and noticed he had a "low, slurred speech and bloodshot/watery eyes."
Cops administered a field sobriety test -- Broner did not perform well -- and he was arrested on site.
Boxing star Adrien Broner was arrested for DUI late Friday night in Miami Beach, TMZ Sports has learned.
We're told the 30-year-old former champ was stopped by police around 8:45 PM local time -- and officers quickly believed Broner was under the influence, so they arrested him for DUI.
Broner was taken to a nearby station where he was awake long enough to take a drowsy mug shot. Bond was set at $1,000 but he's on an 8-hour hold so he'll be behind bars until at least 4 AM on Saturday.
Broner was once considered one of the best prospects in boxing. He was a champ in 4 weight classes -- and Floyd Mayweather took him under his wing. At one point, he gave himself the nickname "About Billions."
Broner is 33-4 as a pro -- but he hasn't won a fight since 2017. Since then, he lost to Manny Pacquiao and Mikey Garcia ... and fought to a draw with Jessie Vargas.