Brad Paisley may be the headliner of his H20 World Tour but he's also the guy who seems to have the most fun enjoying music from openers Justin Moore, Darius Rucker, Steel Magnolia, Easton Corbin and Josh Thompson -- and, yes, even his own band mates. And let's not even get started on the way he goofs around with fans from the minute he steps off the swimming pool ladder (out of virtual water, of course) and jumps onto the stage.

So it's likely no surprise that Brad couldn't resist grabbing his guitar and jumping into the mix during the concert stop in St. Louis Memorial Day weekend, when Steel Magnolia played 'Stop Draggin' My Heart Around,' the classic duet made famous by Tom Petty and Stevie Nicks.

Fans who want a heads-up about Brad's whereabouts should stay tuned to his Twitter page because he might post a clue as to where he's headed. Just a few hours before the St. Louis show, Brad tweeted: "WaterWorld about to fire up. Maybe one of the plaza artists needs another guitar player. I'm gonna audition."

And if you're curious about what's next, consider the tweet Brad posted on June 1 when asked if he made the cut at the "audition" with Steel Magnolia: "No, but 2 more chances, Easton&Josh."

Brad trackers should also stay stay visually alert, too, because during the first show of the tour in Virginia Beach, Va., Brad took a turn on the Chevy ZR1 racing simulator and Chevy H2O FLW fishing simulator plus checked out other 'WaterWorld' entertainment.

"Our goal is to make this the most fun tour ever," Brad told the crowd at the Washington, D.C. area concert. "Did you have fun out there in WaterWorld?"

Our bet is the audiences' cheers still echo in his head.