Forget Madonna - the most memorable moment of Sunday's Super Bowl halftime show came when M.I.A. threw up her middle finger and uttered an expletive to the audience of millions, recalling the raciness of Janet Jackson's 2004 "wardrobe malfunction" and rendering The Material Girl tame by comparison.
The gesture came during a performance of Madonna's new single, "Give Me All Your Luvin," on which M.I.A. raps. Viewers at home saw their screens blur for a second afterwards in a failed attempt to conceal the act.
"The NFL hired the talent and produced the halftime show," NBC spokesman Christopher McCloskey said. "Our system was late to obscure the inappropriate gesture and we apologize to our viewers."
The NFL blamed a failure in NBC's delay system for allowing the gesture to be seen. Spokesman Brian McCarthy said M.I.A. did not do anything similar during rehearsals and the league had no reason to believe she would pull something like that during the actual show.
"The obscene gesture in the performance was completely inappropriate, very disappointing, and we apologize to our fans," McCarthy said.
The British singer M.I.A. is best known for her 2007 hit "Paper Planes," a Grammy nominee for record of the year. Representatives for M.I.A. and Madonna did not immediately respond to ABCNews.com's requests for comment.
The Associated Press contributed to this report.