'We Don't Know What the Future Holds', John Stamos Worries About 'Beach Boys' Mike Love's 'Health Challenges'

After Love appeared weak during a seated performance at Saturday's show in Cincinnati, Ohio, Beach Boys fans were worried.

John Stamos, a longtime friend of Beach Boys frontman Mike Love, said in a lengthy social media post Sunday as he prepared to join the band for Sunday's concert at Nashville's Ryman Hall, "facing serious health challenges."

"Hopefully he'll be doing what he loves for years to come, but we don't know what the future holds," Stamos said of Love.

"Mike is a fighter," Stamos added on Instagram. "Despite doctors, family and friends telling him to focus on his health, he insists on being on stage." He says he needs his band, the audience, his friends and his musicianship surrounding him to lift him up. I played with Mike for 41 years. I never imagined seeing someone larger than life encounter something so human and fragile would affect me so much.

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"The Mike Love we see tonight may not be exactly the Mike we've always known," he tried to prepare fans who expressed concern after Love appeared frailer during a show in Cincinnati, Ohio, on Saturday. But he's still the Mikey we love. Lyrics, optimism, unforgettable concerts, more than 700 hooks he has brought. What he has given me personally is immeasurable."

Stamos went on to talk about what love meant to him personally, as a friend, musician and entertainer, and reflected on their 41-year bond. And he said he wants to "absolutely" be there for his performance with Love and the band in Nashville. Stamos elaborated in a longer Facebook post.

The night before in Cincinnati, the Beach Boys' first show since July, apart from a private performance in Dana Point, Calif., Love seemed somewhat underwhelming, according to a fan video. Stamos led her to a chair at the start of the show, where she sat down to perform, barely breaking out of a few hand gestures before she was triumphantly helped to her feet and belted out the Rocky theme.

The band had canceled several dates prior to the Cincinnati gig due to Love's health concerns.

Stamos addressed the crowd before the Cincinnati show and said, according to a fan video, that Love had "faced some health issues" while there.

He had to cancel some shows. But he won't miss tonight. We kind of said, 'Stay home,' but he said, 'No, I'm going to Cincinnati.' "That's what he loves the most. He loves the audience. He loves the music. He knows how much it means to all of you. We're all here to support him and love him as much as we can. So ladies and gentlemen, please welcome The Beach Boys," Stamos said.

Onstage in Nashville, Love reportedly briefly mentioned that he's "going through health challenges, but I've got to get to Ryman."

The Beach Boys next show is set for November 11th at Disney World, followed by a show in Bristol, Virginia on November 13th.

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