A special evening of country music with Willie Nelson and Alison Krauss & Union Station

Willie Nelson isn’t much for pomp and circumstance. Before the intermission music had even been turned off at the Mann Center on Friday night, the gray-haired Red Headed Stranger had already strolled unceremoniously on stage and slung his guitar around his shoulder, lurching into “Whiskey River” as the members of his band were still situating themselves. That ragged looseness pervaded the entire show, as the country legend tore through shambling renditions of more than two dozen classics, barely stopping for breath from one to the next.

Nelson has always drawn inspiration from jazz, and that influence was clear in his constant disregard for the familiar melodies of his songs, rushing ahead or stretching out a line, his vocals in constant tension with his raw, eclectic guitar work. Despite his renown as a witty songwriter and a singer with an avuncular twang, his fretwork has always been the rough-hewn heart of Nelson’s sound. Veering off in unexpected directions, brusque and halting one moment, stunningly lyrical the next, these six-string inventions were clearly what keeps these songs fresh after, in some cases, more than five decades.

Several members of Nelson’s Family band have been with him as long as much of that repertoire. On piano was Bobbie Lee Nelson, referred to by the 81-year-old singer only as “Little Sister Bobby,” who supplied a traditional country piano sound in contrast to (and occasionally in conflict with) her older brother’s more renegade approach. Drummer Paul English (the co-subject of the hilarious road stories in Nelson’s “Me and Paul”) has been playing with Nelson since 1955, joined on percussion since a 2010 stroke by his brother Billy. Bassist Kevin Smith and harmonica player Mickey Raphael fill out the line-up, all there to keep a steady anchor for Nelson’s meanderings.

After an audience singalong of “Beer for My Horses,” Nelson’s 2003 duet with Toby Keith, a quick “Well, hello there…” served as both greeting to the audience and kick-off to a woozy, last-call-at-the-saloon version of his classic “Ain’t It Funny How Time Slips Away.” Aside from a few thank yous and introductions, that’s about as much patter as Willie spared during the breakneck evening, never letting the last notes of one song die out before crashing into another. “Crazy” was followed by “Night Life,” “On the Road Again” by “Always on My Mind,” “Georgia on My Mind” by “To All the Girls I’ve Love Before,” occasionally punctuated by tossing his trademark red bandana to the crowd (another always seemed to spontaneously reemerge on his forehead). The set also included “Band of Brothers,” the title song from a new album due out this week, and tributes to fellow outlaws Waylon Jennings, Hank Williams, and Billy Joe Shaver.

Earlier in the night, co-headliner Alison Krauss & Union Station was more interested in engaging the audience. Leading her longstanding band, the singer and fiddle player was given to long, droll introductions of her bandmates, including a description of bassist and hunting enthusiast Barry Bales as someone who “likes to get real close to nature and then just stop it.”

Krauss’ hour-long performance followed a brief (and early) opening set by Kacey Musgraves – missed by late arrivals like yours truly. Union Station has long divided its attention between classic bluegrass and a more adult contemporary-leaning brand of countrypolitan that showcases Krauss’ pristine, honeyed vocals, and on Friday they offered both. Krauss sweetly sang a cover of The Foundations’ “Baby, Now That I’ve Found You” and was haloed by a spotlight for a heartbreaking “Ghost in This House,” its spell only broken after the fact, as she recounted the fact that the previous night her son had texted her mid-song to complain about how depressing it was.

But Krauss yielded a considerable amount of that spotlight to her band, especially guitarist/singer Dan Tyminski. Known for the past fourteen years as George Clooney’s singing voice in O Brother Where Art Thou?, Tyminski chalked up another anonymous achievement this year with his vocal contribution to Avicii’s “Hey Brother” – as Krauss said, his voice can now be heard coming out of any Abercrombie & Fitch. The set closed with “Man of Constant Sorrow,” but Tyminski also essayed a truncated “Hey Brother” with dobro player Jerry Douglas.

Douglas himself took a solo turn, showing off his virtuoso playing on a medley of Paul Simon’s “American Tune” and Chick Corea’s “Spain,” the latter including a bit of live looping. Over the course of the two tunes, Douglas managed to wring classic country sounds from the dobro as well as evoking a sitar, a slack-key guitar, and sleek jazz and rock licks. Vocal harmonies were the focus of an encore that included Krauss’ own O Brother contribution, “Down to the River to Pray.”

The evening concluded with all three singers and their bands on stage for an old-fashioned singalong that wouldn’t have felt out of place on the stage of the Ryman Auditorium, except perhaps for Nelson including his marijuana epitaph “Roll Me Up and Smoke Me When I Die” in the midst of gospel favorites “I’ll Fly Away,” “I Saw the Light,” and “Will the Circle Be Unbroken.”