The first-time GRAMMY nominee hit the stage at Sunday's awards ceremony to perform, beginning with a stripped-down performance of "In My Blood" on the piano. Miley Cyrus then joined him to sing Mendes' anthem, the two belting out the tune in perfect unison.
Apple Music's Zane Lowe spoke to Mendes on the GRAMMYs red carpet, prior to his performance, and he talked about performing with Cyrus.
"She just lets it all out, you know?" he said. "You know, like, she doesn’t hold anything back and it’s fully music. You can see, there’s like this thing that happens when she starts singing, her eyes switch over and she’s just like in bliss and when you sing with someone that does that, you also fall into it and it’s just a dream to sing with her."
Mendes teased his performance earlier this week, sharing a backstage photo of Cyrus and him in Dolly Parton-inspired leather jackets:
The 20-year-old also opened up about his pre-GRAMMYs nerves on Instagram, saying, "To be completely honest, true and vulnerable with you guys, I realize that I care so much about what people think, whether it is whoever is sitting in the audience, or what people are thinking online or what people are going to write about the thing after that."
"I realize that's the backwards thing and what I have to truly do is sit down and sing my song and truly connect with it," he added. "In my own heart, be in love with what I’m doing and, in my own heart, get goosebumps from the fact that I'm enjoying what I'm doing so much. Because the only way people in the audience can truly feel is if I'm feeling it, too."
Mendes was nominated for two GRAMMYs this year: "In My Blood" for Song of the Year and his self-titled album for Best Pop Vocal Album.