Merle Haggard was forced to cancel a concert at the last minute on Tuesday (Feb. 2) due to ongoing concerns over his health.

The 78-year-old country legend was scheduled to play a date at the Fox Performing Arts Center in Riverside, Calif., but according to Saving Country Music, he was too ill to take the stage after an opening set from his son, Ben Haggard. The singer's fiddle player came out to announce the news to the disappointed crowd. Haggard later thanked his fans via Facebook for their support during his illness, posting a picture of one man praying behind his bus after his gig was canceled.

"Thank you to the fans who came out tonight in Riverside!" he writes. "Sadly I'm just not strong enough yet. This man was praying behind my bus and made me realize how much you all care. Thank you so much."

Ironically, the show in Riverside was a makeup date for a concert that Haggard postponed in December, when he was hospitalized with double pneumonia.

“I had a double case of pneumonia about the size of grapefruit on each side,” he tells Rolling Stone Country. “I had a pain that went all the way around from my belly button all the way around to my back. I asked the doctor, ‘What was that pain?’ He said, ‘It was death.'”

Haggard’s tour was originally slated to resume Jan. 30 in New Mexico, but he canceled those early shows over concern about his lung capacity and the high elevation. His next show is scheduled at the Saban Theatre in Beverley Hills with Kris Kristofferson for Wednesday (Feb. 3), and he has another concert on the books for Feb. 6 in Las Vegas. So far those shows are still listed on his official website.

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