ST. LOUIS (CBS) — Chuck Berry is resting comfortably at his home near St. Louis, after he collapsed over the weekend while playing a concert in Chicago.

Berry’s agent blames exhaustion for the collapse.

Berry, 84, collapsed Saturday night while playing at the Congress Theater, 2135 N. Milwaukee Ave. His head lay on a keyboard, and he didn’t move for a couple of minutes before he was helped off stage by three people shortly before 10:30 p.m.

WBBM Newsradio 780 traffic reporter Bart Shore was at the show. He knew something was wrong with Berry after only a few songs.

“His guitar wasn’t working quite right earlier in the show. It was out of tune, terribly out of tune. He was having a tough time getting it tuned, so there was a lot of frustration there,” Shore said. “So Chuck sat down at the piano and banged out a couple of notes, turned his back to the audience and slumped over. And everybody in the audience came to a hush.”

A Chicago Fire Department ambulance was called to the theater on the Northwest Side, and emergency crews gave Berry a check-up at the scene, Fire Department Spokesman Joe Roccasalva said. But he said he “felt better” and signed a refusal for further medical treatment, Roccasalva said.

Fans were stunned when they saw Berry collapse.

“About 30 minutes later he came back out and told everybody he was OK, after paramedics had arrived on the scene at the Congress Theatre, and it was a scary moment,” Shore said.

When Berry returned to the stage, most of the auditorium had cleared out. He tuned up his guitar and tried to play before telling the audience he had no strength. He then did a variation of his legendary duck walk off stage.

Berry flew into Chicago after performing two New Year’s Eve shows at B.B. King’s Blues Club and Grill in New York City. The St. Louis-based legend was having trouble connecting with his Chicago-based pick-up band all night.

In a rare moment earlier in the show, Berry even cast aside his guitar and took over the keyboards to play “Let it Rock.” He performed his best-known hits like “Roll Over Beethoven” in slow, disjointed tempos and when he hit stride with more appropriate understated material like “Everyday I Have the Blues,” he stopped halfway through the song. The only tune he was able to muscle through was his 1972 novelty hit, “My Ding-A-Ling,” which featured a call and response with his adoring fans.

Berry is a native and lifelong resident of the St. Louis area, but has connections with Chicago going back to the start of his musical career more than 55 years ago. Most of Berry’s most popular hits, beginning with “Maybellene” in 1955, were recorded at the old Chess Studios on the city’s Near South Side.

In relatively more recent years, one of Berry’s famous concert appearances was at the 1986 Chicago Blues Festival in Grant Park, where he appeared onstage with the Rolling Stones’ Keith Richards.

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