I’m not saying that it’s not an honor to open for Matthew Sweet. “Girlfriend,” the title track and breakout hit from his 1991 album, delighted a generation of pop fans with its singalong chorus and promise of accessibility—a chocolate-coating over the nougat of alternative rock. But when it’s Olivia Mancini opening for Sweet—and at the Birchmere, no less—it feels right, obvious, correct. Mancini is one of the District’s hardest-working musicians. She’s toured for more than a decade, mostly with her longtime band, Olivia & the Mates, but that hasn’t stopped her from playing side gigs with Jarrett Nicolay as Astra Via. Mancini releases a new EP with the Mates at the show, and if it’s anything like the rest of the stuff from her catalog, it’ll be a folk-flavored rock that stands out in a historically angular-hardcore town. No doubt, plenty of people will attend the show to hear Sweet play “Girlfriend.” But others won’t be satisfied until Mancini plays “For Ricky.”

Olivia & the Mates perform with Matthew Sweet at 7:30 p.m. at the Birchmere, 3701 Mount Vernon Ave., Alexandria. $29.50. (703) 549-7500. birchmere.com.