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BELTIN' OUT TUNES
TMZ.com
BELTIN' OUT TUNESJohn C. Reilly ain't just your average movie star -- he's got some decent vocal chops to boot ... with this impromptu performance giving us major flashbacks to one of his roles.
The actor cowboyed up on stage at L.A.'s Fonda Theatre Thursday night ... surprising everyone during Sierra Ferrell's country set -- and as you can see, the crowd goes wild for his performance ... which seems to have come out of nowhere.
TMZ.comJohn was clearly having fun with this ... he's going full-on wacky and animated for this -- and the crowd can't get enough of him, it seems.
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