The Friday before last, Toby Keith performed the seismic 2003 hit “Beer for My Horses” before nearly 20,000 rowdy fans in exurban Mansfield, projecting a video clip of Willie Nelson perfectly singing his portion of the duet. A week later, the real Willie Nelson and his longtime band Family played the same song before nearly 5,000 well-heeled fans in Boston’s cosmopolitan seaport district, using a more homespun technique and technology. Following the quick-stepping show-openers “Whiskey River” and “Still Is Still Moving to Me,” Nelson clipped so fast and loose through “Beer for My Horses” that its identity was certified only when he cupped his ear and the crowd began singing back the chorus, sounding stronger each time around as more fans caught on.
Nelson’s age was partly at issue. The 82-year-old country icon has lost some of the vocal agility he had 12, 25, and even 60 years ago, when he first recorded most of the classic originals and covers in his 75-minute set. But Willie Nelson’s idiosyncratic delivery isn’t just about his aging larynx. After all, the same melodic and rhythmic slippage colored the set’s one guitar instrumental — apparently a version of “Stardust” — with Nelson’s nimble fingering and bold barre chords as sweetly evanescent as a grandfather’s light, quick tousle of his grandson’s hair.
Over the course of two-dozen numbers, the contact high provided by repeated exposure to that woozy delivery proved that Nelson’s artistry is, if anything, more singular than ever. It makes him one of the last American performers who can stride both town and country, sounding sophisticated and down-home at once.
To wrap it up, Nelson ramped up the serendipity with inspired connections: first a drug joke (“All Going to Pot,” the lead single from his fine new duet album with Merle Haggard), then a drug-and-death joke (“Roll Me Up,” and “smoke me when I die”), topped by a country-gospel promise of death transcended (“I’ll Fly Away”).
It probably also helped that Nelson was joined on the last two numbers by six members of Old Crow Medicine Show, which opened the evening with a rousing 70-minute set. After 18 years together, the Nashville outfit has perfected its youthful rendition of an old-time traveling variety act, with two fiddlers hopping in circles during one bluegrass blowout (“Brave Boys”) and lead singer Ketch Secor continually huckstering his Boston knowledge (“Can’t you smell the Boston Harbor? Smells like one big ol’ clam roll rolled up in Revere”). It was a bit of a hard sell, maybe, but also a worthy contrast to the remarkable casual hour to come.