Lars Ulrich's butt has become quite the topic of conversation. Like a certain blue (no white!) dress before it, people can't quite decide what they're seeing in the photo below, reportedly taken by a Met Club member who had access to the stage during Metallica's weekend stop at Rock in Rio USA.

Metallica closed out Saturday's slate of bands with a two-hour performance at the inaugural Rock in Rio on the Las Vegas Strip. Their set stuck to older songs, save for "Lords of Summer," which was released last year as Metallica's first non-Lou Reed music since 2008's Death Magnetic. Meaning, little else was revealed beyond Ulrich's choice in unmentionables.

His rep has now weighed in, telling TMZ an entirely different story. Apparently, Ulrich was the victim of stage lighting, not Victoria's Secret. The photo above is a trick of perspective, the rep says, as the stage's spotlights threw a shadow of the drummer's shirt over his bare rear end.

Wait, that means ... Lars Ulrich played Rock in Rio USA with no underwear on! We could really, really use that long-promised new album from Metallica as a distraction right now.

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