It's been a tough few weeks for Merle Haggard: After postponing some December tour dates due to a bout of double pneumonia that sent him to the hospital and canceling two concerts in New Mexico in late January as he continued to recover, the country icon was forced to cancel a show at the last minute on Tuesday (Feb. 2) because he was still too ill to perform.

According to Saving Country Music, Haggard was scheduled to play the Fox Performing Arts Center in Riverside, Calif., on Tuesday evening; ironically, the show was one of those that had been postponed in December. However, after an opening set from his son, Ben Haggard, the elder Haggard's fiddle player announced that the 78-year-old was too sick to take the stage.

“Thank you to the fans who came out tonight in Riverside! Sadly I’m just not strong enough yet,” Merle Haggard writes on Facebook, also sharing a photo of a fan who was praying behind the country legend's tour bus after the cancellation. “This man ... made me realize how much you all care. Thank you so much.”

On Twitter, Ben Haggard adds that his father "looked down and weeped" when he saw the praying fan. "Moved by the love from the fans!"

In an interview in December, following his hospitalization, Merle Haggard admitted that it was a very good thing he sought treatment when he did.

“I guess I was nearly dead,” Haggard explained. “They couldn’t tell whether I had cancer returned or whether I just had pneumonia. They had to wait until they got the pneumonia under control before we could tell.”

Haggard's next scheduled concert is set for Wednesday (Feb. 3) at the Saban Theatre in Beverley Hills, Calif., with Kris Kristofferson. More information about Haggard's upcoming tour dates is available on his website.

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