Wondering how 2Pac ended up on Kendrick Lamar’s To Pimp A Butterfly? Really, all it took was a phone call.

"It was actually a call from the Top Dawg boss in late November and he said something like, 'Finally I caught you, Kendrick has been living with this interview for a couple of months and it’s sort of the final piece of the puzzle to go through with the album,'" Mats Nileskår, who interviewed Pac in the original clip that was used on Kendrick's "Mortal Man," told XXL.

Nileskår, a Swedish radio host, isn't some random guy who happened to get lucky. He says he's been "doing interviews in the African-American music scene since 1978," and has spoken with everyone from Aretha Franklin and James Brown to Aaliyah and Beyoncé.

As for the chat with 2Pac, he says it happened in 1994, during an extended trip he took to the U.S. The industry vet remembers the day well.

"What I sort of try to do is to put African-American music in a social context, make it a hybrid of music journalism, social reporting and art, to some extent," he explained. "So I remember, what I did was put him in a sort of free space, a free zone. Because he had a hard time, everybody was after him. It was the rape charge; he had recently shot a riot cop in the ass in Atlanta. Everybody was after him. So I tried to put him in a free zone and going off a sort of more or less metaphysical vibe to make him feel freer and so we could talk about the artistry and everything. So I created a space for him to be intense. Or I tried to do that."

And there could be more where this came from, too.

"Maybe it’s a trend," Nileskår said. "Maybe Drake would like to interview Aaliyah, who knows?"

He'll be airing the entire 2Pac interview, including some previously unreleased parts, on his show on Apr. 5.