News Ellen DeGeneres Served as Jennifer Lopez's "Understudy" in Vegas By Olivia Bahou Olivia Bahou Facebook Olivia Solomon is a New York-based writer and editor who covers all things fashion, lifestyle, celebrity, and pop culture. She was previously the Assistant Digital Editor for InStyle, and her work has appeared in many national publications. InStyle's editorial guidelines Updated on September 18, 2017 @ 11:30AM Pin Share Tweet Email When Jennifer Lopez appeared on The Ellen DeGeneres Show on Monday, she didn’t take her place in the talk show's hot seat: Instead, host Ellen DeGeneres went to her—during her residency in Las Vegas. Of course, their interaction was as funny as you’d expect. DeGeneres stopped by Lopez’s dressing room while she was preparing for another night of her Jennifer Lopez: All I Have show and declared that she was there to be J.Lo’s understudy. “We don’t really do, like, understudies … There are no understudies in these type of shows,” Lopez responded. “It’s called Jennifer Lopez: All I Have, and so it’s hard for it to be like, Jennifer Lopez, but it’s not Jennifer Lopez, it’s Ellen.” “This is a concert. This is me singing my songs. It would be hard for somebody else to come in and make believe that they were Jennifer Lopez when they’re not. … It would be weird,” the singer tried to explain. Michael Rozman/Warner Bros. DeGeneres refused to take no for an answer, and tried her best to emulate the performer as she prepared for the dancing-intensive show—vocal warm-ups, stretching, and all. Why Jennifer Lopez Considers A-Rod Her First Good Relationship "Maybe Ever" Lopez even provided some insight into her pre-show routine. “Right now I’ll go to sound check. I’ll take a nap, have some work done on my neck, stuff like that,” she said, explaining that she’d have a light dinner too before the show. DeGeneres, who dubbed herself Lil’ Ellen, even appeared on stage before Lopez’s performance. “I have an announcement to make. Unfortunately, Jennifer Lopez is perfectly healthy and she will be appearing tonight. I will not be playing the part of Jennifer Lopez, so let’s all try to enjoy the show, shall we?” she joked. Michael Rozman/Warner Bros. Watch the clips above to see a peek of Lopez’s jaw-dropping performance, plus DeGeneres’s hilarious cameo during the show.