Kendrick Lamar takes pride in calling himself a writer and not a rapper. Anyone who watched the performance of “Untitled” by Kendrick Lamar on The Stephen Colbert Report last December can only nod in agreement. But if you found out he wrote the spine-tingling, spoken-word reminiscent track just the day before the show, you’d probably stare in disbelief. Kendrick’s producer and band member Terrace Martin was spotted at NPR’s “Microphone Check Show” and was able to give some insight about the performance from December. Sure enough, Kendrick “didn’t want to do nothing that’s already been done,” being that his debut album released a year before, so the TDE MVP got to writing. “We came with that the day before at rehearsal,” said the L.A. native. “He didn’t want to do ‘i.’ Let’s just, you know, fly out to New York. Let’s rehearse in New York and get that energy and do something a little different.” Because the track was fresh from Kendrick’s mental oven, Terrace and beatsmith Thundercat found themselves forgetting the arrangement and freestyled their way through the song (that’s probably where the saxophone solo from Terrace was so raw). Don’t believe us? Just listen. Press play on the interview below and watch the performance in case you need a refresher.