Madonna has reportedly been "brutal" in Super Bowl XLVI rehearsals.
The songstress is taking to the stage at half-time during the National Football League's biggest event this weekend.
Madonna is performing with Nicki Minaj and MIA. The rap stars have collaborated with the singer on her new track Give Me All Your Luvin', which they'll perform.
The 53-year-old is reportedly hell-bent on getting things perfect ahead of the highly-anticipated show, which will screen live on New Zealand screens on Monday at 12pm.
"Madonna has been brutal in rehearsals. Although they've been having a laugh, they've been doing up to 12 hours in a New York studio," a source told British newspaper The Sun.
"She's saying they can sleep after the Super Bowl. She's involved in every aspect of the show, including Minaj and MIA's outfits.
"Nicki has been telling pals it's the most gruelling thing she has ever done and wouldn't expect anything else, calling it an 'epic learning experience'."
Past performers at the Super Bowl include artists such as The Black Eyed Peas, Sir Paul McCartney and Bruce Springsteen.
Super Bowl XLVI is being held at Lucas Oil Stadium in Indianapolis.
Madonna will release her new album MDNA on March 26.