Randy Jackson covered his head and mouthed a repeated "No" after host Ryan Seacrest announced that Toscano received the lowest number of viewer votes after her performance Wednesday of "River Deep — Mountain High."
Toscano, 22, a dark-haired beauty from the Queens borough of New York City managed to remain composed on stage as the judges decried the results.
"I have no idea what happened her. I'm shocked. I'm angry," said judge Jennifer Lopez.
Steven Tyler said viewers were wrong, adding, "She's beautiful. When she sings, she's a bird."
Jackson called her one of the best singers in the show's 10th-season field and warned that "no one is safe" if votes aren't cast for them.
"I'm never upset on this show, and I'm never really mad, but this, like, this makes me mad," Jackson said. "What is going on?"
After choosing "I'll Stand by You" for her swan song, Toscano was embraced by Jacob Lusk, 23, of Compton, Calif., who had landed in the bottom three vote-getters with her and Stefano Langone, 21, of Kent, Wash.
Lusk had held to his gospel roots, replacing his planned version of Marvin Gaye's sexually charged "Let's Get It On" with Michael Jackson's inspirational "Man in the Mirror." Langone sang Percy Sledge's "When a Man Loves a Woman."
Also left to sing another day were Paul McDonald, 26, of Nashville, Tenn.; Casey Abrams, 20, of Idyllwild, Calif.; Haley Reinhart, 20, of Wheeling, Ill.; Lauren Alaina, 16, of Rossville, Ga.; Scotty McCreery, 17, of Garner, N.C., and James Durbin, 22, of Santa Cruz, Calif.
The show Thursday also included a performance of "Real Wild Child" by a shirtless Iggy Pop, with either technical or language glitches causing a loss of sound on occasion.