Classic rock radio came to life at Bold Sphere Music at Champions Square on Thursday night, courtesy of Bad Company and Joe Walsh. Save for a smattering of deep cuts, both veteran acts kept surprises to a minimum in favor of chiseled versions of their hits.

But their tightly constructed showcases still felt organic, as all involved hail from the old school, which dictates that rock music need not be perfect, just powerful, rendered in real time by flesh-and-blood musicians, however grizzled.

As Walsh noted, it was indeed a “nice night for a concert,” with a cool breeze blowing across the expanse of Champions Square along with the abundant guitar solos.

Bad Company arrived onstage precisely at 6:30 p.m. The current tour was to have featured three survivors from the band’s classic 1970s lineup: vocalist Paul Rodgers, drummer Simon Kirke and guitarist Mick Ralphs. However, Ralphs dropped out before the tour with Walsh launched this month.

Black Crowes guitarist Rich Robinson was appointed the last-minute replacement. Robinson’s pedigree of hard Southern rock with a groove was well-suited to the Bad Company catalog. He mostly dealt with rhythm parts as former Heart guitarist Howard Leese, a touring member of Bad Company since 2008, handled the bulk of the solos.

Quite frankly, Ralphs wasn’t missed. Leese, an American by birth, even rocked a Union Jack guitar. In “Ready for Love,” he carved out an especially sharp solo before squaring off with Robinson for an extended, powerful coda. The duo’s six-string harmonies in “Can’t Get Enough” soared.

Rodgers, one of rock’s great voices, was in top form. His pipes are still robust and full-bodied, even-keeled and soulful. And he didn’t parody himself by overdoing the frontman thing. The occasional microphone stand twirl, foray onto the drum riser or turn on a harmonica — during “Feel Like Makin’ Love” — or piano more than sufficed for theatrics. His singing carried the day.

Kirke revisited the fills that have inspired innumerable air drummers. He is not particularly flashy, but he doesn’t need to be while servicing such sturdy, meat-and-potatoes fare. He worked well with Todd Ronning, who built the bass lines that are crucial to so many Bad Company romps. Kirke also stepped out front with an acoustic guitar during “Seagull,” finger-picking the solo himself.

They revived “Gone, Gone, Gone,” one of the few songs written by the late bassist Boz Burrell, and exhumed “Crazy Circles” from the 1979 album “Desolation Angels”; Robinson dressed it up with an acoustic solo as Leese worked a mandolin.

Tough, hard versions of “Rock ’n’ Roll Fantasy” and “Can’t Get Enough” closed the regular set, followed by a swaggering “Bad Company” in the encore. With that, their allotted time was up.

The first words spoken by Walsh upon ambling onstage were a wry “Good morning.”

He has long cultivated a reputation as one of rock’s loons; there was a point in his bleary past when he earned and deserved it. These days, he’s crazy like a fox, playing the goofball onstage while bearing down on a succession of guitars.

As his sixth song of the night, he paid tribute to “my brother and bandmate,” the late Glenn Frey, with “Take It to the Limit.” The video wall behind him alternated pictures of Frey with footage of a guy in a “bat suit” soaring down a mountainside, literally taking it to the limit.

Joe Vitale, one of the two drummers onstage, co-wrote several early Walsh hits. Four backing vocalists provided soul and sass and covered for their leader’s vocal eccentricities. Not that the eccentricities were detrimental — Walsh was just loose enough to make it all seem real.

The epic résumé of his onstage guitar foil, Waddy Wachtel, includes sharing stages and studios with the likes of Jackson Browne, James Taylor, Keith Richards, Stevie Nicks, Bonnie Raitt, Warren Zevon and dozens more. From the opening “Seems to Me” onward, he alternately locked in with Walsh, provided a base upon which the leader could solo or, as in “Rosewood Bitters,” tossed in a slide solo of his own. Together, they put plenty of bite in “In the City” and revved up and elevated “Life in the Fast Lane.”

Walsh introduced “Life’s Been Good” with, “If I would have known I would have to play this song the rest of my life, I would have written something else … possibly.” An onscreen parade of snapshots depicted him with assorted rock-star buddies.

Before “Analog Man,” he copped to being one himself: “I can’t help it.”

However, he updated the “Life’s Been Good” lyric “They write me letters, tell me I’m great” to “They send me emails, tell me I’m great.”

And “Funk #49” was interrupted by a dance party detour that found Walsh and the band boogieing to what sounded like a contemporary dance club track. So maybe he’s a little bit digital after all.

In the encore, he stamped “Rocky Mountain Way” with his signature talk-box guitar effect. It was proudly, and gloriously, analog.

Follow Keith Spera on Twitter, @KeithSpera.