Justin Jones affectionately calls her “L.T.”

And the alt-country crooner recalled playing with her over the years, getting their respective starts at the Grog and Tankard (formerly 2408 Wisconsin Ave NW, DC) in Glover Park.

“We’ve both come a long way,” Justin said Wednesday night at the 9:30 Club. She in question is DC singer-songwriter Laura Tsaggaris.

For her part, Laura is a hard-charging, dedicated musician whose perseverance pays off in a number of rock-and-roll songs that are at turns a little bit country, a little bit folk or a little bit blues. Her joint show with Justin Wednesday was billed as Laura Tsaggaris vs. Justin Jones and the B-Sides, but it was honestly a mutual musician’s concert of admiration.

Laura gave the performance as a showcase to release her new live CD, Live at the Atlas, recorded at the Atlas Performing Arts Center (1333 H St. NE, DC) last September. She played a solid set of some songs featured on the CD as well as some that aren’t. Justin joined her on stage a few times to provide backing vocals in songs like “Dig,” a country tune that reflects on finding yourself. Laura and Justin complement each other well in the live version of the sweetly melancholy song.

Later, she reworked her song “A Matter of Time,” originally a stark strummer, into an upbeat bluesy production, as it appears on Live at the Atlas. That song and the next, “I’m Not in Control,” a lighter song with a catchy recurring whistle, were audience favorites at the show. “I’m in Control,” (a track from her last studio album, 2013’s Everyman, but sadly not on the live album!), was a loose, relaxed rock song that drew cheers from the audience when Laura played it.

Laura’s band kept pace with her dynamics, rolling from song to song gracefully. Saxophonist Elijah Jamal Balbed may not have been on every song, but he was a great addition to those where he joined, such as “Only in Daydreams,” a breezy, jazzy number (also from Everyman and on Live at the Atlas as well). (We can catch Elijah also in the Donvonte McCoy Quintet in upcoming shows at the 18th Street Lounge or with the Chuck Brown Band everywhere.)

As demonstrated by going from country to blues to jazz, Laura is definitely interested in exploring structure and instrumentation. Her rootsy voice and ardent guitar playing run throughout her songs and give them a great deal of consistency, however.

The atmosphere at the 9:30 Club Wednesday made the performance seem like something of an intimate insider’s event, which is really too bad as the concert had a lot to offer to a wide audience. Some research shows that Laura generally plays venues like Gypsy Sally’s (now DC’s premier Americana venue) and Hill Country Backyard Barbecue (our urban spot for roots and country), and I would venture to guess we’ll see her at such a spot soon, ready to rock and roll.

A quick word about Justin Jones: This was also my first time catching the affable troubadour, the only artist signed to 9:30 Club Records, and he too was pretty entertaining. He presented a set of unreleased songs, as featured on the website Noisetrade, including the earnest song, “The River,” a commissioned piece about the Potomac. Unreleased songs, or B-sides, inspired the band he assembled as a group for Wednesday night’s performance. I was most pleasantly surprised personally by their cover of Roxy Music’s “Jealous Guy,” which I not only have never caught live in any performance but also would not ever have guessed was in Justin’s repertoire. He is apparently a man of surprises!