Monday night the knockout rounds of The Voice's eighth season kicked off!

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Blake Shelton paired Sarah Potenza to sing against Brian Johnson.

Potenza sang a very familiar song that's very much a part of The Voice family.

Watch Clips Of 'The Voice' Knockout Rounds Featuring Blake Shelton

During Season 7, Matt McAndrew sang Wasted Love as his original piece during the finals, which is the song that Potenza selected to sing during her knockout round versus Johnson.

Potenza had kind things to say about McAndrew after initially meeting him, which The Voice Twitter shared Monday.

Potenza sent an email to those in charge at The Voice showing such praise for the former Season 7 contestant.

"I don't know why, but I just love that dude," she said in the email and revealed she was "super excited" to sing Wasted Love at her rehearsal.

McAndrew revealed it is "such an honor" that Potenza chose to sang his song. "She killed it!" he beamed.

He was even in the audience during her performance!

Potenza tweeted McAndrew claiming, "the honor was mine" and it was a "dream come true."

Check out Potenza's knockout round performance of Wasted Love below as well as McAndrew's performance of the song from the Season 7 finals.

Tune in on Mondays and Tuesdays starting at 8 p.m. ET for Season 8 of The Voice on NBC.