Guess what Pop star was spotted watching fellow Pop diva Britney Spears perform in concert for her “Femme Fetale” Tour over the weekend in Atlantic City, New Jersey?

Hint: She can call Beyonce up on her “Telephone” at any time!

Lady Gaga!

Photographers snapped Lady Gaga in the crowd Saturday night (Aug 6) in Atlantic City at the Boardwalk Hall watching Pop singer Britney Spears and Young Money femcee Nicki Minaj perform in concert. When her presence was noted by Spears during her set, the crowd erupted with cheers and applause.

Peep the pics (and the footage) below: