In the early '90s, guest rappers showed up in lots of pop songs, typically dropping a verse on the bridge, and sometimes in the outro. Bobby Brown popped up in the Glenn Medeiros hit "She Ain't Worth It
"; Q-Tip on Deee-Lite's "Groove Is in the Heart
"; Michael Bivens on Motownphilly
by Boyz II Men. But the first hit song with a guest rap was "Friends" by Jody Watley in 1989, featuring Eric B. & Rakim.
Rakim was the real deal, a highly respected MC who could write line after line of intricate lyrics and deliver them without breaking a sweat. He drops two verses in this song, addressing a lover who turned against him.
The rap gave the song lots of added flavor, but it kept the song off of many pop radio playlists, as many stations had a strict "no rap" policy. As these rap interludes became more common, more radio stations started to accept them, and for those that didn't, edits were often available with the raps removed. "Friends" was only available with Rakim's rap. Still, it went to #9 on the Hot 100, becoming the first Top 10 pop/rap collaboration.