Prior to his death on April 6Merle Haggard postponed numerous tour dates as he struggled to recover from a bout of pneumonia. However, on Feb. 6, Haggard played what would be one of his final shows, at the Mandalay Bay Ballroom in Las Vegas, Nev. The show included Toby Keith — a last-minute addition to the bill — who has shared his own memories of the night.

"He looked really frail, and I walked him on the stage and said, 'I'll be over here. You call me up whenever you need me,'" Keith recalls to Oklahoma's KFOR-TV. "He made it about eight songs, and he called me up and said, 'Let's do something.'"

In the video above, readers can watch Haggard and Keith perform "Okie From Muskogee." Haggard sings a large part of the song -- after starting it over once, convinced he forgot the first lyrics -- with Keith adding harmonies, until the country icon motions to Keith to take over.

Shortly after the news of Haggard's death broke, actor W. Earl Brown shared his own recollections of this concert, and how Keith's appearance 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. “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 ..."

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 ... Toby came out and sang the rest of the show. Merle gave his last concert. The Strangers got paid. 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.”

Following the news of Haggard’s death, Keith shared on Twitter a photo of himself and Haggard along with a remembrance: “The greatest singer songwriter of my lifetime is gone. Thanks for the music and friendship. R.I.P. Hag – T”

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