Joe McElderry and Cheryl Baker are to perform at a Katherine Jenkins concert on Saturday (09.07.11).
The 'Popstar To Operastar' finalists had been invited to the show judge's performance in Hayward's Heath, Sussex, but the Welsh beauty then dropped the bombshell on them that they would also be taking to the stage.
I have an exciting announcement... As finalists, Joe & Cheryl will be doing a special performance at my concert next Sat, Haywards Heath!
She tweeted: "I have an exciting announcement... As finalists, Joe & Cheryl will be doing a special performance at my concert next Sat, Haywards Heath!"
Despite the shock announcement and impending final, Joe appeared to be relaxed and looking forward to the weekend.
He tweeted: "Run in the park done! Have a quiet night before a busy funfilled week in opera land!!!(sic)"
Katherine also revealed her upset that former Steps singer lost out in a place in the final, despite being one of the favourites to win the show.
She tweeted: "Gutted @ClaireRichards is not in the final - she sang sooo well tonight!
"Claire It's been a delight working with such great talent.You're so fab & we're all going to miss you! C u Sun xx (sic)"
The 'Popstar To Operastar' final will air on ITV1 on Sunday (10.07.11).