Widely circulated video footage shows an unidentified man rushing the stage of the Fonda Theatre and slapping Max across the forehead before being hauled off by security.
The pop star appeared to be momentarily caught off guard by the blow, but resumed dancing as her band continued to play.
Max ― who is currently touring in support of her latest album, “Diamonds & Dancefloors” ― tweeted about the incident early Wednesday.
“He slapped me so hard that he scratched the inside of my eye. He’s never coming to a show again,” she wrote.
Concertgoer Cory Larrabee was among those to share their take on the situation, noting that Max “couldn’t even open her eyes” at first after the slap.
“The guy rushed on stage at the end right when the last song ended,” Larrabee wrote on Twitter. “The security guard tackled him and literally THREW him down the stairs. Wild!!! It happened so fast.”
When contacted by HuffPost, a representative for Max declined further comment.
The stage rush took place just two days after singer Bebe Rexha was struck in the head by a cellphone thrown from the audience as she was performing at The Rooftop at Pier 17, a New York concert venue.
Police arrested Nicolas Malvagna of New Jersey at the scene Sunday and charged him with assault and harassment.
The 27-year-old and his attorney later offered conflicting motives for his actions.
“I was trying to see if I could hit her with the phone at the end of the show because it would be funny,” Malvagna said, according to CBS New York. Speaking to HuffPost, however, attorney Todd Spodek said his client had never meant to hurt Rexha, adding: “As a fan, Mr. Malvagna’s sole intention was to have Ms. Rexha take photos with his phone and return it as a keepsake.”
On Monday, Rexha assured fans via Instagram that she was on the mend, sharing a photo of a black eye along with visible stitches directly above her eyebrow.
“I’m good,” she wrote in the caption, playfully alluding to her single of the same name.