Guess Which DWTS Pro Rocked Out With His Guitar in Los Angeles (PHOTOS)

It's fan fave, Mark Ballas! The DWTS pro was seen on stage at the will.i.am's annual TRANS4M concert benefitting I.Am.Angel foundation in Hollywood last night (February 7). We don't know about you guys, but we wouldn't mind getting serenaded by Mark with that sexy instrument!

Dancing With the Stars Season 16 premieres March 18, 2013 at 8 p.m. ET/PT on ABC.