Being that he's spent decades observing and contributing to hip-hop culture, it's fair to say that Funkmaster Flex has earned the right to speak as an authority. We recently had the chance to catch up with the legendary radio host, a wide-ranging conversation that spanned across a variety of topics -- naturally, freestyles were brought up, given that Flex has witnessed the best of the best putting in work on more than one occasion.

When asked about his favorite freestyle of all time, Flex wasted little time in providing an answer -- one that was perhaps obvious in hindsight given how Earth-shattering it truly was. "Black Thought," he declares, alluding to Thought's epic-ten-minute freestyle that still resonates today.

Black Thought

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"He caught me off guard, man," admits Flex. "I asked him to do a freestyle six months before he disappeared on me. And then he just rang my phone one day and said he was ready. When he got there, he was very relaxed and by himself and I didn’t expect -- a couple of minutes in, I was like this guy is going for it. He going for -- he’s trying to hurt this sh*t. Not only was it a one-take, but there wasn't even a rehearsal he did in there. That was a real one-take. The first time we cut the mic on that's what he did."

"There was no rehearsal," he continues. "We were talking about Mobb Deep and Wu-Tang Clan like before. He just said, ‘Hey, alright, man. I’m ready.’ And then I was like, ‘Oh, sh*t.’ That’s my favorite by far...I think to the people 30 and over he always was [that dude on the mic], but now the 30 and under saw him and appreciated him differently. I did. I appreciated him differently."

All things considered, it's no wonder that rappers were straight-up terrified to hop on a track with Black Thought. For more insight from Funkmaster Flex, be sure to check out our interview right here. 

WATCH: Black Thought makes history on Funk Flex