Way before the frenzy surrounding the release of To Pimp A Butterfly erupted, Kendrick Lamar caused another mini-stir when he performed a moving, untitled, jazzy, funky song as the last musical guest on The Colbert Report. One of his collaborators on the song (and extensively on Butterfly and elsewhere), Terrace Martin, already talked about how Lamar wrote the song the day before they performed it, but now he’s confirmed that the song has never been recorded aside from the live performance.

“It don’t even exist nowhere in the world,” Martin told Complex, “except on The Colbert Report.” Martin said the song was intended to be “just a moment” and won’t see a commercial release at all.

For a refresher of that untitled track, watch Lamar perform it below. In hindsight, it feels like a clear precursor to the direction he took for Butterfly. (Colbert’s Straight Outta Compton joke is still pretty funny, too).