It might just make you "Smile."
While Guardino was voted off the show a few weeks ago, for the May 22 finale he returned for one last performance, and what a heartfelt and beautiful performance it was.
He was joined on stage by the Canadian crooner who wrapped his arm around Guardino in an embrace for the entire performance.
The song they sang was also fitting. A standard that dates all the way back to a 1936 Charlie Chaplin film, "Smile" is all about being positive in the face of sadness.
Given how beautiful their voices are both individually and together, the video really is a must-watch.
What also makes the performance special is that Bublé and Guardino just seem to really enjoy each other's company up on stage. Throughout the song, they keep smiling at each other and embracing for the big musical moments.
When the song finishes in a crescendo, Bublé gestured for the audience to cheer for his partner, which resulted in a standing ovation for the pair. A great show of support for the former contestant!
Bublé wasn't the only Canadian singing their heart out in the competition's finale.
Toronto-born Nicolina Bozzo also got to perform with singer Sara Bareilles after she was eliminated on May 15. They sang "She Used To Be Mine" from the musical Waitress, which was famously the song that Bozzo performed for her audition.
And, given it was the show's finale, the winner was crowned. Kentucky-born Noah Thompson won the show's top spot, performing an original song for the finale.