Sanchez, Joshua Ledet and Elise Testone were voted by viewers into the bottom three on Thursday's edition of the singing competition show.
"This is a ridiculous bottom three," UsMagazine.com reported judge Randy Jackson said. "So wrong!"
Sanchez, who had the least amount of votes, took the stage to perform her last song, prompting Lopez and fellow judges Jackson and Steven Tyler to follow her.
"Gimme that mic!" Lopez said. "This is crazy. You ain't going home! Go sit down."
"This girl is one of the best singers in America ever!" Jackson agreed.
Jackson also offered his opinion about why so good a performer could end up in the bottom three.
"I think what happens, honestly, is people forget to vote and they think their favorites are safe. I mean you saw that bottom three. Oh, my god, it's like, 'What's going on?'" Jackson told E! News after the show.
Still competing on the show against Sanchez are Ledet, Testone, Hollie Cavanagh, Phillip Phillips, Skylar Laine and Colton Dixon.