Haggard passed away on his 79th birthday on Wednesday (06Apr16), and Nelson, who often hit the road and the studio with his fellow stalwart, was among the many stars who shared their condolences on social media, posting a photograph of himself and his pal enjoying a laugh on Twitter.

He wrote the caption: "He was my brother, my friend. I will miss him." He also shared a link to the music video for their song Pancho & Lefty.

And Nelson continues to honour his friend by renaming his SiriusXM radio channel from Willie's Roadhouse to Merle's Roadhouse beginning on Friday (08Apr17).

The weekend-long tribute will feature an encore broadcast of the duo's Django & Jimmie album special hosted by Nelson and Haggard, which was recorded when the album was released last year (15). Also set to air is a two-hour special called Feeling Haggard, as well as an interview that was taped for the Bill Anderson Visits With the Legends show in 2003.

After news of Haggard's passing was revealed on Wednesday, the radio channel's producers immediately began playing 12 continuous hours of Haggard's music and took calls from artists and listeners who paid tribute to the star.