Only 20 minutes into his set, Willie Nelson had already rolled through eight songs.

Delivering them with lean musicianship and the occasional mischievous grin, the 83-year-old musician was a model of stamina Friday night as he unfurled crowd favorites “Whiskey Rose,” “Still is Still Moving to Me,” “Beer for My Horses,” “On the Road Again” and “Always on My Mind” practically without pausing for a breath.

Mirroring Nelson in the endurance department was former President Jimmy Carter, who arrived at Chastain Park Amphitheatre a couple of songs into opener Kris Kristofferson’s performance with wife Rosalynn and a handful of casually dressed Secret Service men in tow.

Carter is an avowed Nelson fan , and he and Rosalynn were spotted standing throughout most of the Red Headed Stranger's set, front row, stage left. When Nelson launched into a concert staple, his rendition of "Georgia on My Mind," a spotlight caught the Carters smiling and singing along (see video below for a snippet).

Along with the presidential couple, about 6,500 other fans tolerated the misty rain that persisted all evening – but not many seemed eager to leave once Nelson hit the stage, clad in black and waving his two arms overhead in greeting.

Nelson’s singing has always been more about character than technicality, so in that sense, his adenoidal tone hasn’t changed. But his spoke-sung delivery of most songs indicated his impatience to get to the good part for him – the guitar playing.

Nelson’s instrument was turned up a bit high in the mix and sometimes he played a step off the beat but always fell back into the groove provided by Billy English on his snare drum – yep, no kit, just a single drum – and bassist Kevin Smith.

Harmonicist Mickey Raphael stayed busy on every song, while Nelson’s sister Bobbie added texture to “Always on My Mind” with her expert piano playing.

In addition to playing a generous set of songs from his 50-plus year career, Nelson asked fans, “What about some Hank Williams?” Before they could respond with a whoop, Nelson was halfway through the first verse of “Jambalaya (on the Bayou).”

During a jam in the song, Nelson edged toward English, swapped his black cowboy hat for a trademark red bandanna (he tossed several into the crowd throughout his set) and segued seamlessly into Williams’ “Hey Good Lookin’” and “Move it On Over.”

Willie Nelson sings "Funny How Time Slips Away" at Chastain. Photo: Melissa Ruggieri/AJC

Credit: Melissa Ruggieri

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Credit: Melissa Ruggieri

The memory of Waylon Jennings was conjured as well with “Mammas Don’t Let Your Babies Grow Up to Be Cowboys” (Jennings and Nelson earned a No. 1 with their 1978 duet).

Nelson continued his rapid-fire blast of hits with “Shoeshine Man” and the song he said used to close his sets “100 years ago” – the aptly titled “The Party’s Over.”

After singing “Funny How Time Slips Away” with a wistful tinge to his voice, Nelson dovetailed into “Crazy,” which included some rough swipes at his guitar that morphed into a thoughtful solo.

When Nelson’s Chastain concert was announced earlier this year, he was set to share the bill with Merle Haggard.

After Haggard's death last month , old Nelson pal Kristofferson stepped in to fill the opening slot, along with Haggard's sons, Ben and Noel.

Backed by Kristofferson’s band, The Strangers, the front threesome alternated at the mic between Haggard classics (“I’m a Lonesome Fugitive” sung by Noel in a smooth country tenor and “Workin’ Man Blues,” handled adeptly by Ben, were standouts) and Kristofferson classics.

At this point, one goes to see Kristofferson to bask in his legacy, not listen to his voice, which vacillated between gruff mumbling on “Me and Bobby McGee” (which he penned in the late-‘60s) and a strained warble on “Sunday Morning Coming Down” and “Why Me.”

The Haggard boys and the band, though, sounded sturdy throughout.

Haggard even received an extra moment of remembrance when, during “Okie from Muskogee,” Noel missed his second verse cue, looked upward and joked, “Sorry, dad.”

He likely wasn’t the only one thinking of Merle at that moment.

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