Nicki Minaj Sued for Battery by Ex-Manager, Rapper Calls Lawsuit 'Frivolous'

6:57 PM PT -- Nicki’s lawyer Judd Burstein tells TMZ … “At this time, no complaint has been served upon Mrs. Petty (Nicki's married name), and therefore, we are unaware of the specific allegations. However, if the lawsuit is as reported by TMZ, it is completely false and frivolous. We are confident that the matter brought by this ex assistant will be resolved swiftly in Mrs. Petty’s favor.”

Nicki Minaj exploded on her day-to-day manager and hit him in the face so hard she knocked his head back and sent his hat flying ... at least according to a new lawsuit.

The "Starships" rapper is being sued by a man named Brandon Garrett, who claims he was working as Nicki's manager during her tour earlier this year when she got physical with him.

In the lawsuit, filed by high-powered trial attorney Thomas Feher and obtained by TMZ, Garrett claims Nicki sent him on an errand after her April 2024 concert in Detroit ... and when he got back he was summoned to her dressing room.

Garrett claims Nicki was inside with other members of her team and she started grilling folks about their job responsibilities. He says she flew into a rage when she learned Garrett had once sent someone else to pick up one of her prescriptions.

In the suit, Garrett claims Nicki screamed at him, "Are you f***ing crazy having him pick up my prescription? You have lost your f***ing mind and if my husband were here, he would knock out your f***ing teeth. You're a dead man walking. You just f***ed up your whole life and you will never be anyone, I'll make sure of it."

Garrett claims Nicki kept screaming at him and told him his "life was over" before striking him on the right side of his face with an open hand. He says the force of the blow caused his head to swing backward and his hat flew off his head.

Nicki's security team then allegedly swarmed in close to Garrett, and he claims Nicki struck him on his right wrist, knocking documents in his hand onto the floor.

Garrett claims Nicki then told him to "get the f*** out" and he says he grabbed his hat and quickly exited the room ... locking himself inside a restroom at Little Caesars Arena.

He says his wrist was throbbing and his face was sore as he called his fiancée to let her know what happened ... claiming he stayed locked in the restroom for hours out of fear for his safety.

Garrett claims Nicki's team didn't let him on the tour bus back to the tour's base in Chicago ... leaving him stranded in Detroit.

He's suing Nicki for assault, battery and intentional infliction of emotional distress ... and he's going after her for damages.

We reached out to Nicki's camp ... so far no word back.