However, on Feb. 6, Haggard played a short set at the Mandalay Bay Ballroom in Las Vegas, Nev., during a show that also included Toby Keith. According to actor W. Earl Brown, Keith was actually a (very) last-minute addition to that bill -- and the country star wound up saving the day.

"Merle had already cancelled months of shows, but this particular booking was a big payday. Merle had to pay his band and crew, so there was no calling in sick for this gig," Brown recalls in a Facebook post. "Toby Keith was in town with his wife to watch some football and have some fun. Toby got word that Merle was in Vegas, so he went to see him …

"Merle was in bad shape. He needed to be in a hospital -- not on a stage; but The Show Must Go On," Brown continues. "Merle would not take charity from anyone, but he did turn to Toby and say, 'How many songs of mine do you know?'

'All of 'em,' answered T.

'All of 'em?'

'Yep. And I won't need a teleprompter.'

'Well, stay nearby.'"

Brown goes on to explain that, just a few songs into his set, "Merle's infected lungs were spent. He couldn't draw enough air to sing any longer."

"'We've, uh, we've got a special guest here tonight …' Toby came out and sang the rest of the show. Merle gave his last concert. The Strangers got paid," Brown recounts. "And the audience, while not realizing it at the time, saw something special.

"Never speak ill of Toby Keith to me," he concludes; "thanks to him, Merle exited the stage with his dignity intact."

Although Brown's original post calls the Mandalay Bay concert "Merle's Final Show," Haggard did perform a couple other shows following that one. However, Brown's point remains: "Whether Vegas was the last show, second-to-last or whatever, the fact remains that when Merle needed a helping hand, he got one, and the audience was not left wanting. Merle was an artist and a showman until the end."

Following the news of Haggard's death, Keith shared on Twitter a photo of himself and Haggard -- the same one that accompanies Brown's Facebook post -- along with a remembrance: "The greatest singer songwriter of my lifetime is gone. Thanks for the music and friendship. R.I.P. Hag - T"

Brown has appeared in numerous TV shows and movies, including Deadwood and Scream. He hosted The Life & Songs of Kris Kristofferson in mid-March.

More Country Stars Remember Merle Haggard

More From TheBoot