A person familiar with the plans for Sunday's halftime show told The Associated Press that R&B star Usher and former Guns 'N Roses guitarist Slash are slated to make surprise appearances.
The person spoke to the AP on condition of anonymity Wednesday, because the musicians' performances were not going to be announced.
Usher and Slash are supposed to join the Black Eyed Peas, who are the main halftime act for Sunday's NFL championship game between the Pittsburgh Steelers and Green Bay Packers at Cowboys Stadium.
Black Eyed Peas member will.i.am is featured on Usher's hit single "O.M.G."
Slash has performed Guns 'N Roses song "Sweet Child o' Mine" on tour with the Black Eyed Peas; he also collaborated with Black Eyed Peas member Fergie on the song "Beautiful Dangerous" last year.
The NFL announced in November that the Black Eyed Peas would be the featured Super Bowl halftime performer. Past halftime acts have included U2, the Rolling Stones, Bruce Springsteen & The E Street Band, Paul McCartney and Prince.