During his Toronto concert, John surprised his audience by welcoming the Canadian crooner onstage to perform his hit Mercy.
And if you thought that alone was a dream for the 18-year-old superfan, Mayer then joined in with a little guitar harmony — before the two transitioned into playing John’s 2008 hit In Your Atmosphere!
Watch Shawn’s wildest dream duet (below)!
In case we didn’t explain just how much this meant to Shawn, just check out what he tweeted afterwards:
Damn. John Mayer is the best. My job is the best. U guys are the best. What an insane night. ❤️
— Shawn Mendes (@ShawnMendes) April 4, 2017
To which his bestie Camila Cabello replied:
We’re so happy for him! We just love seeing dreams come true!
[Image via Daniel Prakopcyk.]