The incredible show also included guest performances by Ja Rule ("I'm Real"), Ne-Yo ("All I Have") and Pitbull ("On the Floor").
The first Jennifer Lopez: All I Have performance boasted quite the star-studded audience. Justin Bieber, Rebel Wilson, Kelly Osbourne, T.I. Gina Rodriguez, Wilmer Valderrama, Nicole Scherzinger, Keenen Ivory Wayans, Derek Hough and Cheryl Burke were there for the triple-threat star's big debut.
"Thanks J.Lo for the amazing concert tonight!!" Wilson Instagrammed along with a video of the performance. "P.S. For some reason I stopped this video right before you winked at me...which SUCKS...but we both know it happened! Congrats!!!"
Bieber and his manager Scooter Braun also got in on the excitement, crooning J. Lo's hit, "Waiting for Tonight."
ET chatted with Lopez at the big show, but she also revealed to us last week that getting ready for her Vegas residency has been quite grueling. "The rehearsals are intense. They're long," she said. "People don't understand all the pieces that go into making a show."
"It's just never-ending," Lopez added. "And it's like, 'Are we going to be ready for Wednesday?' I don't know. It feels like were close but we're also not close. But we'll be ready."