Beyonce is a notorious perfectionist, which may well be why she chose to sing along to a backing track -- not lip sync -- for her performance of 'The Star-Spangled Banner' at President Obama's Inauguration. Her fellow Destiny's Child members have already rushed to her defense, and now her pal Alicia Keys, who performed at Obama's Commander-in-Chief Ball, is joining the ranks of Team Beyhive as well.

"What I do know is that Beyonce is a great performer and she is an incredible artist with a really, really powerful voice," Keys said. "And the one thing that you cannot doubt is that she can sing, you know what I mean? And she absolutely can sing. So all the rest of all the whys or whatever, we know that she can deliver," Keys said firmly. "And she did deliver that song really beautifully."

Beyonce has taken the backlash well. She hasn't addressed it, but is using it to motivate her to work harder at her Super Bowl Halftime Show performance, where she'll open with 'Crazy in Love' before leading into a Destiny's Child medley with Michelle Williams and Kelly Rowland. In fact, she's so serious about "knocking them dead" that she posted some rehearsal photos on Instagram.

In one shot, we see Bey stretching, wearing a Brooklyn Nets v-neck t-shirt -- likely an homage to her hubby, Jay-Z, who owns stock in the team (and in their home court at the Barclays Center in Brooklyn, N.Y.).

In another, we see silhouettes of dancers, which implies that some serious choreography is going into this show. We wouldn't expect anything less from Bey, who remains one of the few superstars who can successfully sing live and dance at the same time and make it look effortless.