PITTSBURGH -- What's a band to do when it reaches its encore and has already played its best songs?
If you're the Avett Brothers, you invite your opening act back on stage for a series of cover tunes.
And so it went Saturday at a close-to-capacity Petersen Events Center, where the Avett Brothers, and their support act, Old Crow Medicine Show, finished memorably with Willie Nelson's "On the Road Again," the century-old hymn "Will the Circle be Unbroken" and the Spaniels' "Goodnite, Sweetheart, Goodnite," replete with a few of the fellas singing the doo-wop-y "it's time to go" part.
It was a visual treat as well as an audio one, seeing two of Americana's top bands squeezed together shoulder-to-shoulder sawing, strumming and plucking away at their old-timey instruments.
Virginia-forged, seven-piece string band Old Crow Medicine Show already had done its warmup duties well, delivering a 45-minute set drenched in energy inherent to its foot-stomping melodies.
"When you're in Pittsburgh, you've got to have two fiddles," frontman Ketch Secor said in his colorful hillbilly drawl following a crowd-rousing double slice of bluegrass violin sandwiched between "Caroline" and "CC Rider."
Earlier, Secor's harmonica playing had put extra octane into "Alabama High Test."
With a string arsenal including standup bass, mandolin, slide guitar and a guitar-banjo hybrid known as a "guitjo," Old Crow served up irresistible barn-burners and a few slower tunes you still could imagine spinning your sweetie around to on a wooden dance floor tucked among some hills and hollers.
As with their outdoor headlining show two years ago at Stage AE, Old Crow was plenty fun, though you get the impression they'd be absolutely magical in a smaller, more intimate setting.
The same is true of the Avett Brothers, the six-man, North Carolina band that plays a folkier brand of Americana emphasizing the shared vocals and harmonies of brothers Seth and Scott Avett.
The Avett Brothers went for the gusto early, launching with the super bouncy, speed-shifting fan favorite "Talk of Indolence." The crowd hadn't caught its breath yet before the Avetts dug into their next selection, a faithful, buoyant cover of John Denver's "Thank God I'm a Country Boy." If you weren't ready to yell "Yee-haw" at that point, then something was wrong with you.
Throughout their two-hour set Joe Kwon spun around his corner of the stage swiping his cello strings. And while not utilized on every song, drummer Mike Marsh made his presence felt.
The Avett Brothers' fourth song, ballad "Good to You," had a pleasing riff reminiscent of the Beatles' "Norwegian Wood." Bassist Bob Crawford got his moment on lead vocals, though it was evident why he's not one of the lead vocalists.
"Down With the Shine" had a nice waltz-y feel, interspersed with some raw-throated vocal interludes from Scott Avett.
I caught my attention drifting a few times mid-set during some slower numbers, though the brothers Avett always snapped me back suddenly, often with their sharp lyrics.
"All My Mistakes," for instance, with its ideal verse in these social media dominated times ("I have some 'friends' they don't know who I am/So I write quotations around the word friends/But I have a couple that have always been there for me"); and "Ten Thousand Words" with its confessional thought-stirrer "We love to talk on things we dont know about..."
The Avett Brothers are a serious bunch for the most part, though they know how to induce smiles, evidenced by the euphoria that erupted with the recognizable banjo notes that lead off "Distraction #74," an amusing anthem about temptation and how trying to keep two girlfriends at once -- without either one knowing -- never ends well.
A couple more lyrical heavy-hitters, "Head Full of Doubt/Road Full of Promises" and "I And Love And You" kept energy levels up leading into the encore. Fans who have followed the Avett Brothers' climb from mid-week Three Rivers Arts Festival band, to arena headliners sang along with the latter song's slow, tender chorus: "I... and love... And you."