Frankie Valli's representative has confirmed that he's "just fine" after concerns were raised about his health.

During a show in Saratoga, California on 3 August, the 90-year-old Four Seasons frontman caused concern when he appeared weak and struggled to lip-sync to his biggest hits during his performance.

A video of the show, which has since gone viral on social media, showed Valli holding onto a handrail as he struggled to climb a short flight of stairs.

The clip also showed the musician lip-syncing to his 1978 hit Grease, but seemingly struggling to keep up with the track.

Soon after the video was posted, fans began questioning why Valli is still performing live.

Almost two weeks after his performance, the Can't Take My Eyes Off You hitmaker's representative confirmed he was fine in a statement to the New York Post.

"Frankie is doing just fine and super happy to still be performing. The audiences are filling venues and listening to some great music," Valli's rep said.

"Frankie is doing what he loves to do at 90," they continued. "We should all be so lucky."

The music legend and The Four Seasons are currently on a farewell tour called The Last Encore, which is due to end in April 2025.

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