The Ultravox frontman and Live Aid mastermind exited the competition after being voted into a sing-off with Pussycat Doll Melody Thornton by viewers.
After performing 'Questa O Quella' from Verdi's Rigoletto again for the competition's judges, Ure initially appeared to have kept his spot on the ITV show, as panelists Rolando Villazon and Vanessa-Mae gave him their backing.
In their comments, Villazon branded Ure as the "performer that felt more comfortable", while Vanessa Mae stated that the 57-year-old "took a risk and really had fun and made me believe".
However, their co-judge Simon Callow sided with Thornton after declaring that she "embraced the extra possibilities" of her performance of 'Habanera' from Carmen, leaving head panellist Katherine Jenkins to cast the deciding vote.
"I feel lilke they definitely both improved," she said. "But the biggest improvement for me and I feel like [the person] if we were to give them another song, they d come out with even more, was Melody."
His fate sealed, Ure joked to host Myleene Klass that he would "have to go back to [his] day job" of "saving the world."
He added: "I've probably done my little bit for opera... no-one wants to go out in the first round, but I think I did a reasonable job."
Bucks Fizz singer Cheryl Baker and X Factor winner Joe McElderry were earlier voted through to the next stage of the contest by viewers.
Erasure lead singer Andy Bell, Steps favourite Claire Richards, Toploader's Joe Washbourn and vocalist Jocelyn Brown will perform for the first time next week.
Popstar To Operastar returns Sunday at 8pm on ITV1.