Late last night, Kendrick Lamar set the rap game on fire by delivering "The Heart Part 4," a song he teased earlier that day (March 23). While K. Dot's bars naturally caused the biggest stir, a few fans also noticed the sound of some very smooth harmonizing at the very beginning of the Axl Folie, Alchemist, SykSense and DJ Dahi-produced track.

If those vocals sound familiar, they should; they belong to Khalid, one of the music world's more critically acclaimed rising stars. The talented 19-year-old confirmed that those, indeed, are his vocals on K. Dot's new track with a tweet late last night.

"I'm so honored to have been apart of this. I can't believe that my voice is on a Kendrick song. This is insane," Khalid wrote in the tweet, which you can see for yourself below.

This is the second time Khalid's vocals have rested beside those of a rap superstar. Last week, the El Paso, Texas singer dropped a remix of his American Teen track, "Location," which features Kehlani and Lil Wayne.

K. Dot first teased "The Heart Part 4" with a cryptic image he uploaded to Instagram yesterday. Plenty of fans jumped to the conclusion that he'd be dropping an album in the very near future, and based on K. Dot telling rappers that they've got "till April the 7th" to get their "shit together," their assumptions might be right.

Twitter Thinks Kendrick Lamar Is Dissing Big Sean on "The Heart Part 4"

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