Hall showed up during the band's soundcheck with guitarist Shane Theriot, a member of the house band on his "Live At Daryl's House" show. They playfully ran through a few songs -- to applause from early-arriving fans -- that they performed later.
Hall played keyboards on Stuart's "Jailhouse," a country-rock foot-stomper that had the packed house clapping along, followed by his gospel-tinged "Slow Train" and "Look At That Girl," an homage to Van Morrison's "Gloria" -- with Stuart, 58, and Hall trading lead vocals.
Hall, 69, then moved center stage for a bouncy version of Hall and Oates "You Make My Dreams Come True."
The crowd hit a fever pitch when Hall and the band completed the cameo with The Band classic "The Weight."
Hall and John Oates took August off from a whirlwind tour that resumes in California on Sept. 3.
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