The musicians look back on their chart-topper “Smooth.”

In celebration of the 20th anniversary of their record-breaking collaboration, Rob Thomas and Carlos Santana reunited onstage in Las Vegas on Saturday night (Sept. 14) at the Mix 94.1/ Bite of Las Vegas music and food festival. They, of course, performed their hit “Smooth” as well as Jimi Hendrix’s “Voodoo Child.”

Backstage Santana and Thomas told Billboard that the longevity of the song comes as no surprise. “It was one of the last songs on the Supernatural record, which featured Eric Clapton, Dave Matthews, Lauryn Hill. I thought it would be the bastard pop son of the album and didn’t expect anything out of it,” Thomas said.

“[When I first heard Rob] I was like, ‘damn, this kid is really soulful and genuine, authentic, true, for real.’ When I heard the song, it had that thing that is above and beyond pedestrian. It's not the flavor of the second. It's going to stay. I immediately knew. This is outside time. This is on another level," Santana added. 

Released on June 29, 1999, “Smooth” stayed on the Billboard charts for 30 weeks and was at the top of the Hot 100 for 12 weeks. Ranking as one of the most successful songs of all time, it won three Grammy Awards including record of the year, song of the year and best pop collaboration. 

“It was this little piece of magic — every now and then all these things come together. We were just coming off of our first record and had a lot of success,” Thomas says. “[Santana] was making this comeback into the radio world. Then you take that, and you sprinkle in a little bit of luck, and there was also a Latin music [moment] happening at the time. I think the culture was open to it. It was all of those little things that [came] together in a really good way. I don't think it's the best song that him or I have ever done. But it was just perfect for us at that time.”

For Santana, from the first time he heard “Smooth,” he knew it was the complete package — a blend of the spiritual and divine. “I could tell that this particular presentation was going to touch a lot of people's hearts, especially women, and make them feel validated, celebrated and honored. It changes the energy of the room,” he said.

Thomas is the first to admit that the song has taken on its own personality over the years. “John Mayer and I figure that between his 'Daughters' and 'Smooth' that we are now going to be at every wedding until the end of time.” Recently, Santana and Thomas dueted onstage in Arizona and the fans went crazy so a Las Vegas reunion seemed to be “super” natural fit.

“[Carlos] was supposed to fly in town tomorrow because he's getting ready to start his residency again — it just worked out. He came in a day early so we could hook up,” Thomas said.

“When we play the song it is like S-E-X, spiritually speaking,” Santana added. Santana’s eight-year residency at Las Vegas’ House of Blues “An Intimate Evening with Santana: Greatest Hits Live” picks up again Sept. 18 with dates announced through May 2020. 

Thomas revealed that the two have stayed close since the single broke in June 1999 and that Santana is one of his closest friends. “We talk every other day, or at least text. We have this long text thread going where we just send each other goofy pictures, and affirmations, and stuff. He's just a really funny guy,” he revealed. Thomas has been out on his “Chipped Tooth” tour since May. “It's to the point where you go through tired, and now you're on the other side of that, and now you're invincible,” he said, noting that in honor of the year ’20, his group Matchbox Twenty will come together for a three-month summer tour.