She let out a curse word and raised a manicured middle finger.
It's hardly the kind of thing that would shock fans of British singer M.I.A., who's known for her controversial, political lyrics and provocative performances.
But for the Super Bowl, it was considered a big no-no.
M.I.A.'s guest performance at halftime, in which she raised her middle finger and appeared to sing "I don't give a (expletive)" during Madonna's song Give Me All Your Luvin' has been likened to the championship game's 2004 scandal when Janet Jackson exposed her nipple in an apparent wardrobe malfunction.
Broadcaster NBC quickly issued an apology for M.I.A.'s performance.
"We apologize for the inappropriate gesture that aired during halftime," NBC spokesman Christopher McCloskey said, according to USA Today.
Brian McCarthy, spokesman for the National Football League, also offered regrets.
"The obscene gesture in the performance was completely inappropriate, very disappointing, and we apologize to our fans," he said.
As The Guardian newspaper points out, however, "it was probably more shocking seeing M.I.A. performing a rehearsed dance routine than flipping the bird."
In 2009, M.I.A. stunned audiences of the Grammy Awards when she sampled her hit song Paper Planes while nine months pregnant. Three years prior, she was reportedly denied entry into the U.S., which some speculated was because of her political lyrics. And her 2010 Born Free video caused a stir for its depiction of police violence against redheads, an apparent statement on the mistreatment of minorities.
Was M.I.A.'s Super Bowl act of defiance really horrifying, or merely ho-hum?