"They became friends and started jamming together and that kind of thing," says Ryan Dusick, Maroon 5's drummer.
Later, by the time Maroon 5 was working on its funk-laden debut, Songs About Jane, Mayer was already finding success with Room for Squares. He liked a rough copy of Maroon 5's new album enough to invite them as his opener last summer.
This year, Maroon 5 parlayed that into a full tour with Mayer. But the band, which has been endlessly -- and erroneously -- compared to the Red Hot Chili Peppers, isn't quite ready to front one on its own.
"You know, we were intending to try to put together our own tour, and that would be quite an undertaking," says Dusick. "It is another level of production value that I don't know if we're ready for -- the PA system, the lighting. This turned out to be a really good deal."