State Champs welcomed All Time Low's Alex Gaskarth to the stage for a special guest appearance at the Vans Warped Tour stop in Ventura, California, on Sunday. Thankfully, a handful of fans grabbed footage of the onstage collab. Check it out!

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This isn't the first time Gaskarth has teamed with State Champs for a tune. ATL fans were able to witness Champs frontman Derek DiScanio join the band on "Dear Maria, Count Me In" last year at a So Wrong, It's Right anniversary gig.

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Check out the video for State Champs' new single "Criminal," below, and sound off in the comments. Did you catch Alex Gaskarth join the band onstage at Warped? Are you planning to attend the tour's final full cross-country run? Let us know!

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