Willie Nelson and SARA EVANS were named late additions to the Super Bowl festivities in Arizona. The country couple were scheduled to perform a duet before the big sports showdown between the New York Giants and New England Patriots on Sunday (03Feb08) as WENN went to press. Evans was to perform a 'tailgate' party concert outside the University of Phoenix Stadium, where the game is being played later today (03Feb08) before joining Nelson for a rendition of Mammas, Don't Let Your Babies Grow Up to Be Cowboys as part of the pre-match telecast. Alicia Keys will perform a pre-game concert on the field, and American Idol winner Jordin Sparks will sing the national anthem. Rockers Tom Petty + the Heartbreakers will perform a 12-minute concert during the half-time celebration.