It's the one and only song in this country you can't screw up the lyrics to (not even a little bit). Oh well, maybe no one was watching. Christina addresses the mistake:

By Us Weekly

February 7, 2011 10:30 AM ET

Christina Aguilera is well aware that she made a boo-boo while singing the National Anthem opening up Sunday's Super Bowl XLV. Singing Francis Scott Key's "The Star-Spangled Banner" live at Cowboys Stadium in Arlington, Texas, the singer, 30, flubbed the lyrics – trilling "what so proudly we watched" instead of the correct lyrics, "o'er the ramparts we watched."

So what happened?

Aguilera opened up about the gaffe in a statement. "I got so caught up in the moment of the song that I lost my place," says the star. "I can only hope that everyone could feel my love for this country and that the true spirit of its anthem still came through."

Prior to the performance, the veteran entertainer said she was psyched to sing the patriotic ditty before millions of viewers.

"I have been performing the anthem since I was seven years old and I must say the Super Bowl is a dream come true...I am really excited to be part of such an iconic event."

via Christina Aguilera Explains National Anthem Flub | Rolling Stone Music.