The song "Smooth" from Santana and Rob Thomas was a massive hit in 1999. The song spent 12 weeks at #1, won three Grammys, and became Carlos Santana's biggest hit ever. "Smooth" had a lot of factors going for it: a great dance beat, the combination of a classic rock star and a successful current vocalist, and that soaring guitar. It worked well on pop, rock, Latin, and adult contemporary radio playlists. It was the perfect first single for Santana's comeback album Supernatural, as it was designed to be. But the road to that success was not exactly 'smooth.' Ticking off the requirements for a hit single, producers rejected songwriter Itaal Shur's lyrics and enlisted Rob Thomas to write new ones for Shur's tune. Thomas sang his lyrics on the demo before he was considered for the actual recording.
Santana: When I listened to the lyrics and heard, “It’s a hot one,” those lyrics are outside of time and gravity. I thought we had entered a place of immortality. But with all respect to Rob, I said, “I’m having a little challenge believing you that what you’re singing is true.”
Matt Serletic (producer): At some point, Carlos wasn’t sure about Rob. He was on the fence. My first conversation with Carlos was about that, like, “Rob’s really a believable singer. He can bring it.” Carlos wanted to be assured, as any artist is with whatever doubts they have. He’s a spiritual guy, and I guess he got a good vibe from the conversation. He said, “I trust you. Let’s do this.”
Davis: Carlos says, “We have to have him. He has to do it. He’s perfect.” I said, “Well, easier said than done. The guy records for another record company.”
The twists and turns required to get "Smooth" recorded were worth all the trouble as the song became a radio staple over the next several years. Read the story of "Smooth" at Rolling Stone. -via Metafilter
Also: There is an alternative oral history, which may be less accurate but more entertaining.