On Music's Biggest Night, tensions flared between two Canadian pop stars.

Though The Weeknd wasn't nominated for an award, he and the robotic duo of Daft Punk lit up the Grammy stage by performing "Starboy" and "I Feel It Coming." Despite four nominations, Justin Bieber came away empty-handed, though he likely wasn't too bothered, as he didn't even show up for the show. 

Instead, Bieber spent his night cruising around town while taking fan questions on Instagram Live. "Favorite song of the moment?" asked one of Bieber's passengers, relaying questions from the Beliebers. After pausing for several seconds, Bieber replied, "'Starboy' by The Weeknd."

It was a peculiar answer, considering that The Weeknd is currently dating Bieber's longtime ex, Selena Gomez. A few weeks ago, a TMZ reporter asked Bieber if he was able to listen to a song by The Weeknd. "Starboy" was not in his rotation then. "Hell no, I can't listen to a Weeknd song," he laughed. "That shit's wack." 

Immediately after naming The Weeknd's hit single, though, Bieber and the rest of the car broke out into hysterical laughter, thus insinuating high levels of shade. "Oh that was too funny," he said after regaining his composure. 

Thus far, The Weeknd hasn't made an effort to clap back at his countryman. He's got the girl, after all. While he was getting trolled by the Biebs, he and Gomez were coupled up at Rihanna's after-party. If the tensions continue to escalate, these two studs could find themselves in the most sensational beef of the season.